Citations
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This panel provides information on past usage of this interatomic potential (IP) powered by the OpenKIM Deep Citation framework. The word cloud indicates typical applications of the potential. The bar chart shows citations per year of this IP (bars are divided into articles that used the IP (green) and those that did not (blue)). The complete list of articles that cited this IP is provided below along with the Deep Citation determination on usage. See the Deep Citation documentation for more information.
212 Citations (140 used)
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USED (definite) J. Sun et al., “Rebuilding the Strain Hardening at a Large Strain in Twinned Au Nanowires,” Nanomaterials. 2018. link Times cited: 10 Abstract: Metallic nanowires usually exhibit ultrahigh strength but lo… read moreAbstract: Metallic nanowires usually exhibit ultrahigh strength but low tensile ductility, owing to their limited strain hardening capability. Here, our larger scale molecular dynamics simulations demonstrated that we could rebuild the highly desirable strain hardening behavior at a large strain (0.21 to 0.31) in twinned Au nanowires by changing twin orientation, which strongly contrasts with the strain hardening at the incipient plastic deformation in low stacking-fault energy metals nanowires. Because of this strain hardening, an improved ductility is achieved. With the change of twin orientation, a competing effect between partial dislocation propagation and twin migration is observed in nanowires with slant twin boundaries. When twin migration gains the upper hand, the strain hardening occurs. Otherwise, the strain softening occurs. As the twin orientation increases from 0° to 90°, the dominating deformation mechanism shifts from slip-twin boundary interaction to dislocation slip, twin migration, and slip transmission in sequence. Our work could not only deepen our understanding of the mechanical behavior and deformation mechanism of twinned Au nanowires, but also provide new insights into enhancing the strength and ductility of nanowires by engineering the nanoscale twins. read less USED (definite) S. M. Rassoulinejad-Mousavi and Y. Zhang, “Interatomic Potentials Transferability for Molecular Simulations: A Comparative Study for Platinum, Gold and Silver,” Scientific Reports. 2018. link Times cited: 33 USED (definite) S. Vigonski et al., “Au nanowire junction breakup through surface atom diffusion,” Nanotechnology. 2017. link Times cited: 26 Abstract: Metallic nanowires are known to break into shorter fragments… read moreAbstract: Metallic nanowires are known to break into shorter fragments due to the Rayleigh instability mechanism. This process is strongly accelerated at elevated temperatures and can completely hinder the functioning of nanowire-based devices like e.g. transparent conductive and flexible coatings. At the same time, arranged gold nanodots have important applications in electrochemical sensors. In this paper we perform a series of annealing experiments of gold and silver nanowires and nanowire junctions at fixed temperatures 473, 673, 873 and 973 K (200 °C, 400 °C, 600 °C and 700 °C) during a time period of 10 min. We show that nanowires are especially prone to fragmentation around junctions and crossing points even at comparatively low temperatures. The fragmentation process is highly temperature dependent and the junction region breaks up at a lower temperature than a single nanowire. We develop a gold parametrization for kinetic Monte Carlo simulations and demonstrate the surface diffusion origin of the nanowire junction fragmentation. We show that nanowire fragmentation starts at the junctions with high reliability and propose that aligning nanowires in a regular grid could be used as a technique for fabricating arrays of nanodots. read less USED (definite) A. P’alink’as et al., “Moiré superlattices in strained graphene-gold hybrid nanostructures,” Carbon. 2016. link Times cited: 13 USED (definite) A. Maier, D. Mari, I. Tkalčec, and R. Schaller, “Grain Boundary Relaxation in Bi-Crystals: Mechanical Spectroscopy and Molecular Dynamics Simulations,” Archives of Metallurgy and Materials. 2015. link Times cited: 1 Abstract: Different Au-Ag-Cu samples have been studied by mechanical s… read moreAbstract: Different Au-Ag-Cu samples have been studied by mechanical spectroscopy. Both polycrystals and bi-crystals show a relaxation peak at 800 K, accompanied by an elastic modulus change. Since this peak is absent in single crystals it is related to the presence of grain boundaries. Molecular dynamics simulations reveal two microscopic mechanisms, when a shear stress is applied onto a Sigma 5 grain boundary: at 700 K, the boundary migrates perpendicularly to the boundary plane under an external stress. At 1000 K, only sliding at the boundary is observed. These two mechanisms acting in different temperature intervals are used to model the mechanic response of a polycrystal under an applied stress. The models yield expressions for the relaxation strength Delta and for the relaxation time tau as a function of the grain size. A comparison with the mechanical spectroscopy measurements of polycrystals and the bi-crystals show that the grain boundary sliding model reproduces correctly the characteristics of the grain boundary peak. read less USED (high confidence) C. Winkeljohn, S. M. Shahriar, E. Seker, and J. Mason, “Simulated surface diffusion in nanoporous gold and its dependence on surface curvature,” Computational Materials Science. 2023. link Times cited: 0 USED (high confidence) A. D. wael et al., “Three Approaches for Representing the Statistical Uncertainty on Atom-Counting Results in Quantitative ADF STEM.,” Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada. 2022. link Times cited: 1 Abstract: A decade ago, a statistics-based method was introduced to co… read moreAbstract: A decade ago, a statistics-based method was introduced to count the number of atoms from annular dark-field scanning transmission electron microscopy (ADF STEM) images. In the past years, this method was successfully applied to nanocrystals of arbitrary shape, size, and composition (and its high accuracy and precision has been demonstrated). However, the counting results obtained from this statistical framework are so far presented without a visualization of the actual uncertainty about this estimate. In this paper, we present three approaches that can be used to represent counting results together with their statistical error, and discuss which approach is most suited for further use based on simulations and an experimental ADF STEM image. read less USED (high confidence) E. Pervolarakis, G. Tritsaris, P. Rosakis, and I. Remediakis, “Machine Learning for the edge energies of high symmetry Au nanoparticles,” Surface Science. 2022. link Times cited: 1 USED (high confidence) Q. Huang et al., “Twinning-assisted dynamic adjustment of grain boundary mobility,” Nature Communications. 2021. link Times cited: 17 USED (high confidence) E. A. Irmak, P. Liu, S. Bals, and S. V. Aert, “3D Atomic Structure of Supported Metallic Nanoparticles Estimated from 2D ADF STEM Images: A Combination of Atom‐Counting and a Local Minima Search Algorithm,” Small Methods. 2021. link Times cited: 12 Abstract: Determining the 3D atomic structure of nanoparticles (NPs) i… read moreAbstract: Determining the 3D atomic structure of nanoparticles (NPs) is critical to understand their structure‐dependent properties. It is hereby important to perform such analyses under conditions relevant for the envisioned application. Here, the 3D structure of supported Au NPs at high temperature, which is of importance to understand their behavior during catalytic reactions, is investigated. To overcome limitations related to conventional high‐resolution electron tomography at high temperature, 3D characterization of NPs with atomic resolution has been performed by applying atom‐counting using atomic resolution annular dark‐field scanning transmission electron microscopy (ADF STEM) images followed by structural relaxation. However, at high temperatures, thermal displacements, which affect the ADF STEM intensities, should be taken into account. Moreover, it is very likely that the structure of an NP investigated at elevated temperature deviates from a ground state configuration, which is difficult to determine using purely computational energy minimization approaches. In this paper, an optimized approach is therefore proposed using an iterative local minima search algorithm followed by molecular dynamics structural relaxation of candidate structures associated with each local minimum. In this manner, it becomes possible to investigate the 3D atomic structure of supported NPs, which may deviate from their ground state configuration. read less USED (high confidence) B. Lim et al., “A convolutional neural network for defect classification in Bragg coherent X-ray diffraction,” npj Computational Materials. 2021. link Times cited: 6 USED (high confidence) Q. Zhu, Q. Huang, H. Zhou, and J. Wang, “Inclination-governed deformation of dislocation-type grain boundaries,” Journal of Materials Research. 2021. link Times cited: 2 Abstract: Grain boundaries (GBs) in polycrystalline materials are freq… read moreAbstract: Grain boundaries (GBs) in polycrystalline materials are frequently curved, which differ from the well-documented planar GBs in terms of structure and dynamics. However, the physical origin of curvature-controlled GB deformation remains unclear. Here, combining in situ transmission electron microscopy (TEM) nanomechanical testing and atomistic simulation, we rationalize the fundamental influences of GB inclination on the deformation of curved dislocation-type GBs in face-centered cubic metals. Non-uniform motion of curved GB is revealed and attributed to the inclination-dependent dislocation configurations, which simultaneously change the energy and mobility of GBs. An inclination-governed GB model extending from the classic dislocation theory is further established via geometric analyses, where a universal inclination threshold of 35° is deduced to precisely predict the deformation behaviors of curved GBs. These findings enhance our mechanistic understanding of GB-mediated plasticity, shedding light on the structural design of metallic materials via precise GB engineering. read less USED (high confidence) C. Seidl, J. Hörmann, and L. Pastewka, “Molecular Simulations of Electrotunable Lubrication: Viscosity and Wall Slip in Aqueous Electrolytes,” Tribology Letters. 2021. link Times cited: 5 USED (high confidence) P. Liu et al., “Three-dimensional atomic structure of supported Au nanoparticles at high temperature.,” Nanoscale. 2021. link Times cited: 9 Abstract: Au nanoparticles (NPs) deposited on CeO2 are extensively use… read moreAbstract: Au nanoparticles (NPs) deposited on CeO2 are extensively used as thermal catalysts since the morphology of the NPs is expected to be stable at elevated temperatures. Although it is well known that the activity of Au NPs depends on their size and surface structure, their three-dimensional (3D) structure at the atomic scale has not been completely characterized as a function of temperature. In this paper, we overcome the limitations of conventional electron tomography by combining atom counting applied to aberration-corrected scanning transmission electron microscopy images and molecular dynamics relaxation. In this manner, we are able to perform an atomic resolution 3D investigation of supported Au NPs. Our results enable us to characterize the 3D equilibrium structure of single NPs as a function of temperature. Moreover, the dynamic 3D structural evolution of the NPs at high temperatures, including surface layer jumping and crystalline transformations, has been studied. read less USED (high confidence) M. Mikelani, M. Panjepour, and A. Taherizadeh, “Investigation on mechanical properties of nanofoam aluminum single crystal: using the method of molecular dynamics simulation,” Applied Physics A. 2020. link Times cited: 3 USED (high confidence) Q. Zhu et al., “Metallic nanocrystals with low angle grain boundary for controllable plastic reversibility,” Nature Communications. 2020. link Times cited: 49 USED (high confidence) D. Zhukhovitskii and V. Zhakhovsky, “Thermodynamics and the structure of clusters in the dense Au vapor from molecular dynamics simulation.,” The Journal of chemical physics. 2020. link Times cited: 9 Abstract: Clusters of atoms in dense gold vapor are studied via atomis… read moreAbstract: Clusters of atoms in dense gold vapor are studied via atomistic simulation with the classical molecular dynamics method. For this purpose, we develop a new embedded atom model potential applicable to the lightest gold clusters and to the bulk gold. Simulation provides the equilibrium vapor phases at several subcritical temperatures, in which the clusters comprising up to 26 atoms are detected and analyzed. The cluster size distributions are found to match both the two-parameter model and the classical nucleation theory with the Tolman correction. For the gold liquid-vapor interface, the ratio of the Tolman length to the radius of a molecular cell in the liquid amounts to ∼0.16, almost exactly the value at which both models are identical. It is demonstrated that the lightest clusters have the chain-like structure, which is close to the freely jointed chain. Thus, the smallest clusters can be treated as the quasi-fractals with the fractal dimensionality close to two. Our analysis indicates that the cluster structural transition from the solid-like to chain-like geometry occurs in a wide temperature range around 2500 K. read less USED (high confidence) D. Holec, P. Dumitraschkewitz, D. Vollath, and F. Fischer, “Surface Energy of Au Nanoparticles Depending on Their Size and Shape,” Nanomaterials. 2020. link Times cited: 38 Abstract: Motivated by often contradictory literature reports on the d… read moreAbstract: Motivated by often contradictory literature reports on the dependence of the surface energy of gold nanoparticles on the variety of its size and shape, we performed an atomistic study combining molecular mechanics and ab initio calculations. We show that, in the case of Au nanocubes, their surface energy converges to the value for (001) facets of bulk crystals. A fast convergence to a single valued surface energy is predicted also for nanospheres. However, the value of the surface energy is larger in this case than that of any low-index surface facet of bulk Au crystal. This fact can be explained by the complex structure of the surface with an extensive number of broken bonds due to edge and corner atoms. A similar trend was obtained also for the case of cuboctahedrons. Since the exact surface area of the nanoparticles is an ill-defined quantity, we have introduced the surface-induced excess energy and discuss this quantity as a function of (i) number of atoms forming the nano-object or (ii) characteristic size of the nano-object. In case (i), a universal power-law behaviour was obtained independent of the nanoparticle shape. Importantly, we show that the size-dependence of the surface energy is hugely reduced, if the surface area correction is considered due to its expansion by the electronic cloud, a phenomenon specifically important for small nanoparticles. read less USED (high confidence) V. Samsonov, I. Talyzin, A. Kartoshkin, and M. V. Samsonov, “Prediction of Segregation in Binary Metal Nanoparticles: Thermodynamic and Atomistic Simulations,” Physics of Metals and Metallography. 2019. link Times cited: 5 USED (high confidence) S. Xu, J. Mianroodi, A. Hunter, I. Beyerlein, and B. Svendsen, “Phase-field-based calculations of the disregistry fields of static extended dislocations in FCC metals,” Philosophical Magazine. 2019. link Times cited: 39 Abstract: ABSTRACT In the continuum context, the displacements of atom… read moreAbstract: ABSTRACT In the continuum context, the displacements of atoms induced by a dislocation can be approximated by a continuum disregistry field. In this work, two phase-field (PF)-based approaches and their variants are employed to calculate the disregistry fields of static, extended dislocations of pure edge and pure screw character in two face-centred cubic metals: Au and Al, which have distinct stable stacking fault energy and elastic anisotropy. A new truncated Fourier series form is developed to approximate the generalised stacking fault energy (GSFE) surface, which shows significant improvement over the previously employed Fourier series form. By measuring the intrinsic stacking fault (ISF) width and partial dislocation core size in different ways, the PF-based disregistry fields are quantitatively compared against those predicted by molecular statics. In particular, two new measures for the ISF widths are proposed and shown to overcome drawbacks of the more commonly used standards in the literature. Our calculations also show that continuum formulation of the elastic energy and the GSFE for a homogeneous surface can successfully characterise the core structure. Last, our comparisons highlight the significance of including the gradient energy in the free energy formulation when an accurate description of the dislocation core structure is desired. read less USED (high confidence) S. Chavoshi and S. Xu, “Nanoindentation/scratching at finite temperatures: Insights from atomistic-based modeling,” Progress in Materials Science. 2019. link Times cited: 37 USED (high confidence) Q. Zhu et al., “In situ atomistic observation of disconnection-mediated grain boundary migration,” Nature Communications. 2019. link Times cited: 298 USED (high confidence) J. Li, Y. Xian, H. Zhou, R. Wu, G. Hu, and R. Xia, “Microstructure-sensitive mechanical properties of nanoporous gold: a molecular dynamics study,” Modelling and Simulation in Materials Science and Engineering. 2018. link Times cited: 26 Abstract: The present paper aims to investigate the microstructural di… read moreAbstract: The present paper aims to investigate the microstructural differences of models used in nanoporous metals and research on the mechanical response of various morphological architectures, including cube, gyroid, diamond and stochastic bicontinuous structures. By using molecular dynamics simulations, the influential parameters of architectural morphology, relative density and ligament diameter on the mechanical properties of nanoporous gold under uniaxial tension are presented and further compared with current constitutive theory and experimental results of the literature. The differences among those structures are critically demonstrated and addressed. Results present that the Young’s modulus as a function of relative density and the yield strength as a function of ligament diameter both display power-law relation but the scaling exponents vary with the microstructures. The modulus of stochastic bicontinuous structures is in better agreement with the experimental results. The relationship between yield stress and relative density is approximately linear, indicating the yielding behavior may be dominated by the yielding of ligaments in the process of deformation. These results promise much for the design of nanoporous structures with tunable, desirable mechanical properties stemming from various microstructures. read less USED (high confidence) M. Karim et al., “Ultrafast Pulsed Laser Induced Nanocrystal Transformation in Colloidal Plasmonic Vesicles,” Advanced Optical Materials. 2018. link Times cited: 9 Abstract: Plasmonic vesicle consists of multiple gold nanocrystals wit… read moreAbstract: Plasmonic vesicle consists of multiple gold nanocrystals within a polymer coating or around a phospholipid core. As a multifunctional nanostructure, it has unique advantages of assembling small nanoparticles (<5 nm) for rapid renal clearance, strong plasmonic coupling for ultrasensitive biosensing and imaging, and near‐infrared light absorption for drug release. Thus, understanding the interaction of plasmonic vesicles with light is critically important for a wide range of applications. In this paper, a combined experimental and computational study is presented on the nanocrystal transformation in colloidal plasmonic vesicles induced by the ultrafast picosecond pulsed laser. Experimentally observed merging and transformation of small nanocrystals into larger nanoparticles when treated by laser pulses is first reported. The underlying mechanisms responsible for the experimental observations are investigated with a multiphysics computational approach featuring coupled electromagnetic/molecular dynamics simulation. This study reveals for the first time that combined nanoparticle heating and laser‐enhanced Brownian motion is responsible for the observed nanocrystal merging. Correspondingly, laser fluence, interparticle distance, and presence of water are identified as the most important factors governing the nanocrystal transformation. The guidelines established from this study can be employed to design a host of biomedical and nanomanufacturing applications involving laser interaction with plasmonic nanoparticles. read less USED (high confidence) Y. Gan and Z. Sun, “Intrinsic damping for ultrafast laser-excited acoustic vibrations of single gold nanorods,” Journal of Nanoparticle Research. 2018. link Times cited: 2 USED (high confidence) S. Xu, M. Latypov, and Y. Su, “Concurrent atomistic-continuum simulations of uniaxial compression of gold nano/submicropillars,” Philosophical Magazine Letters. 2018. link Times cited: 8 Abstract: ABSTRACT In this work, uniaxial compression of nano/submicro… read moreAbstract: ABSTRACT In this work, uniaxial compression of nano/submicropillars in Au with the initial diameter D between 26.05 and 158.53 nm was modelled by concurrent atomistic-continuum simulations. Two models with distinct surface facets were employed to explore the surface facets-dependent extrinsic size effects on the plastic deformation of pillars. It is found that (i) the yielding in pillars with smooth surfaces was controlled by dislocation nucleation from the two ends of the pillars, and (ii) in pillars with faceted surfaces, dislocations were initiated from the sharp edges on the surface. As a result of the differences in the plastic deformation mechanism between the two models, the yield stress decreased exponentially and increased nearly linearly with respect to an increasing D in pillars with smooth and faceted surfaces, respectively. read less USED (high confidence) A. Backer et al., “Three-dimensional atomic models from a single projection using Z-contrast imaging: verification by electron tomography and opportunities.,” Nanoscale. 2017. link Times cited: 37 Abstract: In order to fully exploit structure-property relations of na… read moreAbstract: In order to fully exploit structure-property relations of nanomaterials, three-dimensional (3D) characterization at the atomic scale is often required. In recent years, the resolution of electron tomography has reached the atomic scale. However, such tomography typically requires several projection images demanding substantial electron dose. A newly developed alternative circumvents this by counting the number of atoms across a single projection. These atom counts can be used to create an initial atomic model with which an energy minimization can be applied to obtain a relaxed 3D reconstruction of the nanoparticle. Here, we compare, at the atomic scale, this single projection reconstruction approach with tomography and find an excellent agreement. This new approach allows for the characterization of beam-sensitive materials or where the acquisition of a tilt series is impossible. As an example, the utility is illustrated by the 3D atomic scale characterization of a nanodumbbell on an in situ heating holder of limited tilt range. read less USED (high confidence) L. Yang, J. Bian, and G. Wang, “Impact of atomic-scale surface morphology on the size-dependent yield stress of gold nanoparticles,” Journal of Physics D: Applied Physics. 2017. link Times cited: 19 Abstract: Size-dependent mechanical properties have been revealed for … read moreAbstract: Size-dependent mechanical properties have been revealed for nanowires, nanopillars and nanoparticles. On the surfaces of these nanosized elements, discrete atomic-scale steps will be naturally generated, however their impact on the mechanical properties and deformation has seldom been a concern. In this paper, large-scale molecular dynamics simulations are conducted to calculate the yield stress of gold nanoparticles under compression. In addition to absolute particle size, atomic-scale surface morphology induces significant fluctuation of the yield stress. An analytical relation is advanced to predict the yield stress of nanoparticles accounting for the influence of both size and surface morphology, which agrees well with atomic simulations. This study illuminates an important mechanism in nanosized elements, atomic-scale surface steps. read less USED (high confidence) D. Holec et al., “Atomistic Modeling‐Based Design of Novel Materials ,” Advanced Engineering Materials. 2017. link Times cited: 11 Abstract: Modern materials science increasingly advances via a knowled… read moreAbstract: Modern materials science increasingly advances via a knowledge‐based development rather than a trial‐and‐error procedure. Gathering large amounts of data and getting deep understanding of non‐trivial relationships between synthesis of materials, their structure and properties is experimentally a tedious work. Here, theoretical modeling plays a vital role. In this review paper we briefly introduce modeling approaches employed in materials science, their principles and fields of application. We then focus on atomistic modeling methods, mostly quantum mechanical ones but also Monte Carlo and classical molecular dynamics, to demonstrate their practical use on selected examples. read less USED (high confidence) Y. Hu, P. Kumar, Y. Xuan, B. Deng, M. Qi, and G. Cheng, “Controlled and Stabilized Light–Matter Interaction in Graphene: Plasmonic Film with Large‐Scale 10‐nm Lithography,” Advanced Optical Materials. 2016. link Times cited: 25 Abstract: Graphene–plasmonic metal nanostructures have great potential… read moreAbstract: Graphene–plasmonic metal nanostructures have great potential as optical metamaterials with strong light–matter interactions for applications in energy harvesting, biochemical sensing, and plasmonics. Currently, large‐scale fabrication of graphene–plasmonic hybrid systems have the following bottlenecks to realization of their full potential: 1) the geometry of metal nanostructures is not well controlled, 2) the substrates are rigid, and 3) low chemical and thermal stability of plasmonic metal nanostructures. Top‐down fabrication of a free‐standing hybrid film is demonstrated with graphene veiling for flexible‐substrate‐supported engineered plasmonic nanoarrays. Large‐scale graphene–plasmonic nanoengineered hybrid structures with the capability to generate large optical‐field enhancement, such as ultrasharp 3D pyramids, 10‐nm V‐grooves, and nanotrenches (10–100 nm), are nanoimprinted from physical‐vapor‐deposited nanocrystalline thin films on flexible substrates by laser‐shock‐induced 10‐nm lithography. Anisotropic light–matter interactions with tunable field enhancement, hot electron transfer at the graphene–metal interface, and optical reflectance in the graphene are shown in a sub‐100‐nm nanoengineered metal structure. The application of such hybrid films is demonstrated in trace‐level direct detection of antibiotics from their waste containers. This hybrid structure has excellent stability in a reactive environment (sulfur) and at elevated temperatures (ca. 300 °C). These 10‐nm lithography enabled graphene–plasmonic nanosystems will stimulate development of many novel devices in a hybrid, tunable hot‐carrier‐surface plasmonic concept. read less USED (high confidence) J. Mianroodi, A. Hunter, I. Beyerlein, and B. Svendsen, “Theoretical and computational comparison of models for dislocation dissociation and stacking fault/core formation in fcc crystals,” Journal of The Mechanics and Physics of Solids. 2016. link Times cited: 43 USED (high confidence) C. Deng and F. Sansoz, “A new form of pseudo-elasticity in small-scale nanotwinned gold,” Extreme Mechanics Letters. 2016. link Times cited: 12 USED (high confidence) R. Rezaei, C. Deng, H. Tavakoli-Anbaran, and M. Shariati, “Deformation twinning-mediated pseudoelasticity in metal–graphene nanolayered membrane,” Philosophical Magazine Letters. 2016. link Times cited: 29 Abstract: In this study, we investigated the deformation behaviour of … read moreAbstract: In this study, we investigated the deformation behaviour of metal–graphene nanolayered composites for five face-centred cubic metals under compression using molecular dynamics simulations. It was found that by increasing the thickness of the individual metal layers, the composite strength increased, while the deformation mechanism changed from buckling to deformation twining in Cu, Au and Ag, which was absent in the monolithic form of those metals of the same orientation and size. The deformation twinning was found to be enabled by the graphene layer, which introduced pseudoelasticity and shape memory effects in the nanolayered membrane with more than 15% recoverable compressive strain. read less USED (high confidence) G. Zograf et al., “Modeling of formation mechanism and optical properties of Si/Au core-shell nanoparticles,” 2016 Days on Diffraction (DD). 2016. link Times cited: 2 Abstract: Fabrication of metal/semiconductor (“hybrid”) nanoparticles … read moreAbstract: Fabrication of metal/semiconductor (“hybrid”) nanoparticles is still a challenge due to the absence of methods of a metal core coating by crystalline semiconductor shell. We propose a novel principle of formation of a core-shell nanoparticle made of liquid silicon and gold droplets. Molecular dynamics simulations of the droplets behavior demonstrates that the core-shell structure with a gold core and a silicon shell can be formed if the droplets remain in the liquid state until final material redistribution. The main driven force in this process is surface tension governed by surface energies of the droplets, where silicon tends to cover gold due to lower surface energy. Taking into account this mechanism of core-shell nanoparticles formation, we provide numerical modelling, which demonstrates the resulting nanoparticle posses enhanced local electromagnetic field, high Purcell factor and flexible power patterns of scattered light. read less USED (high confidence) Z.-L. Liu, J.-S. Sun, R. Li, X.-L. Zhang, and L. Cai, “Comparative Study on Two Melting Simulation Methods: Melting Curve of Gold,” Communications in Theoretical Physics. 2016. link Times cited: 9 Abstract: Melting simulation methods are of crucial importance to dete… read moreAbstract: Melting simulation methods are of crucial importance to determining melting temperature of materials efficiently. A high-efficiency melting simulation method saves much simulation time and computational resources. To compare the efficiency of our newly developed shock melting (SM) method with that of the well-established two-phase (TP) method, we calculate the high-pressure melting curve of Au using the two methods based on the optimally selected interatomic potentials. Although we only use 640 atoms to determine the melting temperature of Au in the SM method, the resulting melting curve accords very well with the results from the TP method using much more atoms. Thus, this shows that a much smaller system size in SM method can still achieve a fully converged melting curve compared with the TP method, implying the robustness and efficiency of the SM method. read less USED (high confidence) M. Aramfard and C. Deng, “Interaction of shear-coupled grain boundary motion with crack: Crack healing, grain boundary decohesion, and sub-grain formation,” Journal of Applied Physics. 2016. link Times cited: 14 Abstract: Stress-driven grain boundary motion is one of the main mecha… read moreAbstract: Stress-driven grain boundary motion is one of the main mechanisms responsible for microstructural evolution in polycrystalline metals during deformation. In this research, the interaction of shear-coupled grain boundary motion (SCGBM) in face-centered cubic metals with crack, which is a common type of structural defects in engineering materials, has been studied by using molecular dynamics simulations in simple bicrystal models. The influences of different parameters such as metal type, temperature, grain boundary structure, and crack geometry have been examined systematically. Three types of microstructural evolution have been identified under different circumstances, namely, crack healing, grain boundary decohesion, and sub-grain formation. The underlying atomistic mechanisms for each type of SCGBM-crack interaction, particularly grain boundary decohesion and crack healing, have also been examined. It is found that crack healing is generally favoured during the SCGBM-crack interaction at relatively high... read less USED (high confidence) X. Liu, 刘小明, Z. Liu, and 魏悦广, “Ploughing friction and nanohardness dependent on the tip tilt in nano-scratch test for single crystal gold,” Computational Materials Science. 2015. link Times cited: 12 USED (high confidence) C. G. Zhang, Y. Li, W. Zhou, L. Hu, and Z. Zeng, “Anti-radiation mechanisms in nanoporous gold studied via molecular dynamics simulations,” Journal of Nuclear Materials. 2015. link Times cited: 20 USED (high confidence) Y. Gan, Z. Sun, and Z. Chen, “Extensional vibration and size-dependent mechanical properties of single-crystal gold nanorods,” Journal of Applied Physics. 2015. link Times cited: 10 Abstract: The vibrational responses of single-crystal gold nanorods wi… read moreAbstract: The vibrational responses of single-crystal gold nanorods with different sizes and aspect ratios caused by femtosecond laser heating have been simulated, using a numerical method that integrates the two-temperature model into molecular dynamics. The fundamental extensional periods of nanorods are derived by analyzing the simulated responses of nanorods and then used to determine the elastic modulus of nanorods with the finite element calculations. It is shown that the modulus of nanorods increases and approaches the value of bulk gold with the increasing nanorod width. The dispersion curves for the fundamental extensional mode of nanorods as obtained by the analytical solutions and the finite element analysis are compared, confirming that the extensional periods of nanorods with an aspect ratio as small as ∼2.4 are fairly well described by the theory based on the long-wavelength limit. read less USED (high confidence) M. Dupraz, G. Beutier, D. Rodney, D. Mordehai, and M. Verdier, “Signature of dislocations and stacking faults of face-centred cubic nanocrystals in coherent X-ray diffraction patterns: a numerical study1,” Journal of Applied Crystallography. 2015. link Times cited: 31 Abstract: Crystal defects can be identified by their fingerprint in co… read moreAbstract: Crystal defects can be identified by their fingerprint in coherent X-ray diffraction patterns. Realistic defects in face-centred cubic nanocrystals are studied numerically, revealing various signatures in diffraction patterns depending on the Miller indices and providing an identification method. read less USED (high confidence) G. Grochola, I. Snook, and S. Russo, “Predicting large area surface reconstructions using molecular dynamics methods.,” The Journal of chemical physics. 2014. link Times cited: 4 Abstract: In this paper we discuss a new simulation method that can be… read moreAbstract: In this paper we discuss a new simulation method that can be used to predict preferred surface reconstructions of model systems by Molecular Dynamics (MD). The method overcomes the limitations imposed by periodic boundary conditions for finite boundary MD simulations which can normally prevent reconstructions. By simulating only the reconstructed surface layer and by removing the periodic boundary effects and the free energy barriers to reconstruction, the method allows surfaces to reconstruct to a preferred structure. We test the method on three types of surfaces: (i) the Au(100) and Pt(100) hexagonally reconstructed surface, (ii) the Au(111) herringbone surfaces, and (iii) the triangularly reconstructed Ag surface layer on a Pt(111) substrate and find the method readily finds lower surface energy reconstructions as preferred by the potential. read less USED (high confidence) E. Hosseinian and O. Pierron, “Quantitative in situ TEM tensile fatigue testing on nanocrystalline metallic ultrathin films.,” Nanoscale. 2013. link Times cited: 72 Abstract: A unique technique to perform quantitative in situ transmiss… read moreAbstract: A unique technique to perform quantitative in situ transmission electron microscopy (TEM) fatigue testing on ultrathin films and nanomaterials is demonstrated. The technique relies on a microelectromechanical system (MEMS) device to actuate a nanospecimen and measure its mechanical response. Compared to previously demonstrated MEMS-based in situ TEM techniques, the technique takes advantage of two identical capacitive sensors on each side of the specimen to measure electronically elongation (with nm resolution) and applied force (with μN resolution). Monotonic and fatigue tests were performed on nanocrystalline gold ultrathin film specimens that were manipulated and fixed onto the MEMS device without the use of a focused ion-beam microscope (and therefore, importantly, without any associated surface damage). The major advantage of the technique is its capability to use TEM imaging solely for high magnification microstructural observations while the MEMS device provides continuous tracking of the material's response, thereby expanding the capabilities of MEMS-based techniques towards more complex in situ TEM nanomechanical tests, such as fatigue tests. read less USED (high confidence) J. W. Wang, S. Narayanan, J. Y. Huang, Z. Zhang, T. Zhu, and S. Mao, “Atomic-scale dynamic process of deformation-induced stacking fault tetrahedra in gold nanocrystals,” Nature Communications. 2013. link Times cited: 105 USED (high confidence) X.-Y. Sun, G. Xu, X. Li, X.-Q. Feng, and H. Gao, “Mechanical properties and scaling laws of nanoporous gold,” Journal of Applied Physics. 2013. link Times cited: 170 Abstract: Nanoporous metals are a class of novel nanomaterials with po… read moreAbstract: Nanoporous metals are a class of novel nanomaterials with potential applications in many fields such as sensing, catalysis, and fuel cells. The present paper is aimed to investigate atomic mechanisms associated with the uniaxial tensile deformation behavior of nanoporous gold. A phase field method is adopted to generate the bicontinuous open-cell porous microstructure of the material. Molecular dynamics simulations then reveal that the uniaxial tensile deformation in such porous materials is accompanied by an accumulation of stacking faults in ligaments along the loading direction and their junctions with neighboring ligaments, as well as the formation of Lomer–Cottrell locks at such junctions. The tensile strain leads to progressive necking and rupture of some ligaments, ultimately resulting in failure of the material. The simulation results also suggest scaling laws for the effective Young's modulus, yield stress, and ultimate strength as functions of the relative mass density and average ligament size ... read less USED (high confidence) H. Wei and Y. Wei, “Interaction between a screw dislocation and stacking faults in FCC metals,” Materials Science and Engineering A-structural Materials Properties Microstructure and Processing. 2012. link Times cited: 32 USED (high confidence) Y. Zhang and H.-C. Huang, “Controllable introduction of twin boundaries into nanowires,” Journal of Applied Physics. 2010. link Times cited: 12 Abstract: Crystalline nanowires particularly metallic nanowires with t… read moreAbstract: Crystalline nanowires particularly metallic nanowires with twin boundaries have higher strength than those without. Achieving the higher strength requires controllable introduction of twin boundaries, which is impossible at the present. Turning the impossibility to a possibility, this paper proposes a mechanism of controllably introducing twin boundaries into crystalline nanowires by design; and demonstrates its feasibility using molecular dynamics simulations. This mechanism relies on the combination of mechanical torsion and local melting (and subsequent solidification). Under torsion, a nanowire twists by an angle along its axis. Upon local melting, the torsion concentrates at the molten zone. With proper twist angle for each crystal orientation, a geometrically necessary twin boundary forms controllably during solidification of the molten zone. Repeating this process generates controllable patterns of twin boundaries in nanowires. read less USED (high confidence) C. Deng and F. Sansoz, “Effects of twin and surface facet on strain-rate sensitivity of gold nanowires at different temperatures,” Physical Review B. 2010. link Times cited: 36 Abstract: We use classical molecular-dynamics simulations to examine t… read moreAbstract: We use classical molecular-dynamics simulations to examine the strain-rate sensitivity of single-crystalline and twinned Au nanowires (NWs) with a diameter of 12.3 nm deformed in tension at temperatures between 10 K and 450 K. It is found that the strain-rate sensitivity above 100 K is significantly smaller in twinned Au NWs with perfectly circular cross-section than in similar NWs without twins, while the activation volume remains in the same range of $1{b}^{3}--15{b}^{3}$ with $b$ the magnitude of Burgers vector. This behavior is markedly different from that generally observed in bulk face-centered cubic metals where addition of nanoscale twins increases both strength and strain-rate sensitivity. Furthermore, our simulations show a threefold decrease in strain-rate sensitivity in twinned Au NWs with zigzag morphology constructed by assembly of {111} surface facets in comparison to the different types of circular Au NWs. The rate-controlling deformation mechanisms related to surface dislocation emission and twin-slip interaction, and their dependence on temperature and surface morphology are analyzed in detail. The combination of ultrahigh strength and decreased sensitivity to strain-rate predicted above 100 K in twinned Au NWs with faceted surface morphology holds great promise for creating metallic nanostructures with increased failure resistance to extreme loading conditions. read less USED (high confidence) C. Deng and F. Sansoz, “Fundamental differences in the plasticity of periodically twinned nanowires in Au, Ag, Al, Cu, Pb and Ni,” Acta Materialia. 2009. link Times cited: 136 USED (high confidence) C. Deng and F. Sansoz, “Near-ideal strength in gold nanowires achieved through microstructural design.,” ACS nano. 2009. link Times cited: 117 Abstract: The ideal strength of crystalline solids refers to the stres… read moreAbstract: The ideal strength of crystalline solids refers to the stress at elastic instability of a hypothetical defect-free crystal with infinite dimensions subjected to an increasing load. Experimentally observed metallic wires of a few tens of nanometers in diameter usually yield far before the ideal strength, because different types of surface or structural defects, such as surface inhomogeneities or grain boundaries, act to decrease the stress required for dislocation nucleation and irreversible deformation. In this study, however, we report on atomistic simulations of near-ideal strength in pure Au nanowires with complex faceted structures related to realistic nanowires. The microstructure dependence of tensile strength in face-centered cubic Au nanowires with either cylindrical or faceted surface morphologies was studied by classical molecular dynamics simulations. We demonstrate that maximum strength and steep size effects from the twin boundary spacing are best achieved in zigzag Au nanowires made of a parallel arrangement of coherent twin boundaries along the axis, and {111} surface facets. Surface faceting in Au NWs gives rise to a novel yielding mechanism associated with the nucleation and propagation of full dislocations along {001}110 slip systems, instead of the common {111}112 partial slip observed in face-centered cubic metals. Furthermore, a shift from surface dislocation nucleation to homogeneous dislocation nucleation arises as the twin boundary spacing is decreased below a critical limit in faceted nanowires. It is thus discovered that special defects can be utilized to approach the ideal strength of gold in nanowires by microstructural design. read less USED (high confidence) C. Deng and F. Sansoz, “Size-dependent yield stress in twinned gold nanowires mediated by site-specific surface dislocation emission,” Applied Physics Letters. 2009. link Times cited: 79 Abstract: Large-scale molecular dynamics simulations were performed to… read moreAbstract: Large-scale molecular dynamics simulations were performed to demonstrate the synergistic effects of twin boundaries and free surfaces on dislocation emission in gold nanowires under tensile loading. It is revealed that the addition of nanoscale twins to crystalline nanowires can act to either increase or decrease their resistance to slip in tension, depending on both sample diameter and number of twins per unit length. Site-specific surface dislocation emission and image forces due to twin boundaries are used to explain the size-dependence of yield stress in twinned gold nanowires. read less USED (high confidence) C. Deng and F. Sansoz, “Uniaxial Compression Behavior of Bulk Nano-twinned Gold from Molecular Dynamics Simulation,” MRS Proceedings. 2007. link Times cited: 3 Abstract: Parallel molecular dynamics simulations were used to study t… read moreAbstract: Parallel molecular dynamics simulations were used to study the influence of pre-existing growth twin boundaries on the slip activity of bulk gold under uniaxial compression. The simulations were performed on a 3D, fully periodic simulation box at 300 K with a constant strain rate of 4×10 7 s −1 . Different twin boundary interspacings from 2 nm to 16 nm were investigated. The strength of bulk nano-twinned gold was found to increase as the twin interspacing was decreased. However, strengthening effects related to the twin size were less significant in bulk gold than in gold nanopillars. The atomic analysis of deformation modes at the twin boundary/slip intersection suggested that the mechanisms of interfacial plasticity in nano-twinned gold were different between bulk and nanopillar geometries. read less USED (low confidence) A. Hua and J. Zhao, “A unified disconnection model of stress-driven grain boundary migration in nanocrystalline metals,” Journal of the Mechanics and Physics of Solids. 2023. link Times cited: 0 USED (low confidence) T. Fedyaeva, S. Mathesan, A. Bisht, Z. Liang, D. Mordehai, and E. Rabkin, “The effects of composition and microstructure on compressive strength of Ag-Au nanoparticles,” Acta Materialia. 2023. link Times cited: 0 USED (low confidence) Y. F. Woguem, P. Godard, J. Durinck, and S. Brochard, “Elastic energy and interactions between twin boundaries in nanotwinned gold,” Computational Materials Science. 2023. link Times cited: 0 USED (low confidence) M. H. Saffarini, T. Sewell, Y.-C. Su, and Z. Chen, “Atomistic study of the impact response of bicontinuous nanoporous gold as a protection medium: Effect of porous-nonporous interface on failure evolution,” Computational Materials Science. 2023. link Times cited: 0 USED (low confidence) M. Settem, C. Roncaglia, R. Ferrando, and A. Giacomello, “Structural transformations in Cu, Ag, and Au metal nanoclusters.,” The Journal of chemical physics. 2023. link Times cited: 1 Abstract: Finite-temperature structures of Cu, Ag, and Au metal nanocl… read moreAbstract: Finite-temperature structures of Cu, Ag, and Au metal nanoclusters are calculated in the entire temperature range from 0 K to melting using a computational methodology that we proposed recently [M. Settem et al., Nanoscale 14, 939 (2022)]. In this method, Harmonic Superposition Approximation (HSA) and Parallel Tempering Molecular Dynamics (PTMD) are combined in a complementary manner. HSA is accurate at low temperatures and fails at higher temperatures. PTMD, on the other hand, effectively samples the high temperature region and melts. This method is used to study the size- and system-dependent competition between various structural motifs of Cu, Ag, and Au nanoclusters in the size range 1-2 nm. Results show that there are mainly three types of structural changes in metal nanoclusters, depending on whether a solid-solid transformation occurs. In the first type, the global minimum is the dominant motif in the entire temperature range. In contrast, when a solid-solid transformation occurs, the global minimum transforms either completely to a different motif or partially, resulting in the co-existence of multiple motifs. Finally, nanocluster structures are analyzed to highlight the system-specific differences across the three metals. read less USED (low confidence) Z. Zhang, Q. Huang, and H. Zhou, “High-entropy alloy nanocrystals with low-angle grain boundary for superb plastic deformability and recoverability,” International Journal of Plasticity. 2023. link Times cited: 3 USED (low confidence) Z. Fang, B. Li, S. Tan, S. Mao, and G. Wang, “Revealing shear-coupled migration mechanism of a mixed tilt-twist grain boundary at atomic scale,” Acta Materialia. 2023. link Times cited: 0 USED (low confidence) L. Kong, G. Cao, H. Zhou, and J. Wang, “In Situ Observation of High Bending Strain Recoverability in Au Nanowires,” Crystals. 2023. link Times cited: 0 Abstract: Metallic nanowires (NW) usually exhibit unique physical, mec… read moreAbstract: Metallic nanowires (NW) usually exhibit unique physical, mechanical, and chemical properties compared to their bulk counterparts. Despite extensive research on their mechanical behavior, the atomic-scale deformation mechanisms of metallic nanowires remain incompletely understood. In this study, we investigate the deformation behavior of Au nanowires embedded with a longitudinal twin boundary (TB) under different loading rates using in situ nanomechanical testing integrated with atomistic simulations. The Au nanowires exhibit a recoverable bending strain of up to 27.5% with the presence of TBs. At low loading rates, the recoverable bending is attributed to the motion of stacking faults (SFs) and their interactions with TBs. At higher loading rates, the formation of high-angle grain boundaries and their reversible migration become dominant in Au nanowires. These findings enhance our understanding of the bending behavior of metallic nanowires, which could inspire the design of nanodevices with improved fatigue resistance and a large recoverable strain capacity. read less USED (low confidence) N. Hara, G. Tchoudinov, A. Filipponi, and A. D. Cicco, “Local structure of solid and liquid Au as a function of temperature by x-ray absorption spectroscopy,” Physical Review B. 2023. link Times cited: 0 USED (low confidence) J. Cobeña-Reyes, T. Ye, and A. Martini, “Simulations of Subnanometer Scale Image Contrast in Atomic Force Microscopy of Self-Assembled Monolayers in Water,” Chemical & Biomedical Imaging. 2023. link Times cited: 0 Abstract: Achieving high-resolution images using dynamic atomic force … read moreAbstract: Achieving high-resolution images using dynamic atomic force microscopy (AFM) requires understanding how chemical and structural features of the surface affect image contrast. This understanding is particularly challenging when imaging samples in water. An initial step is to determine how well-characterized surface features interact with the AFM tip in wet environments. Here, we use molecular dynamics simulations of a model AFM tip apex oscillating in water above self-assembled monolayers (SAMs) with different chain lengths and functional groups. The amplitude response of the tip is characterized across a range of vertical distances and amplitude set points. Then relative image contrast is quantified as the difference of the amplitude response of the tip when it is positioned directly above a SAM functional group vs positioned between two functional groups. Differences in contrast between SAMs with different lengths and functional groups are explained in terms of the vertical deflection of the SAMs due to interactions with the tip and water during dynamic imaging. The knowledge gained from simulations of these simple model systems may ultimately be used to guide selection of imaging parameters for more complex surfaces. read less USED (low confidence) H. Iteney, T. Cornelius, O. Thomas, and J. Amodeo, “Load versus displacement-controlled nanocompression: Insights from atomistic simulations,” Scripta Materialia. 2023. link Times cited: 1 USED (low confidence) H. Haouas, L. E. Atouani, K. Sbiaai, and A. Hasnaoui, “Size and temperature effects on surface energy of Au and Fe nanoparticles from atomistic simulations,” Computational Materials Science. 2022. link Times cited: 1 USED (low confidence) Z. Fang, J. Xiao, S. Tan, C. Deng, G. Wang, and S. Mao, “Atomic-scale observation of dynamic grain boundary structural transformation during shear-mediated migration,” Science Advances. 2022. link Times cited: 8 Abstract: Grain boundary (GB) structural change is commonly observed d… read moreAbstract: Grain boundary (GB) structural change is commonly observed during and after stress-driven GB migration in nanocrystalline materials, but its exact atomic scale transformation has not been explored experimentally. Here, using in situ high-resolution transmission electron microscopy combined with molecular dynamics simulations, we observed the dynamic GB structural transformation stemming from reversible facet transformation and GB dissociation during the shear-mediated migration of faceted GBs in gold nanocrystals. A reversible transformation was found to occur between (002)/(111) and Σ11(113) GB facets, accomplished by the coalescence and detachment of (1¯1¯1)/(002)-type GB steps or disconnections that mediated the GB migration. In comparison, the dissociation of (002)/(111) GB into Σ11(113) and Σ3(111) GBs occurred via the reaction of (111)/(111¯)-type steps that involved the emission of partial dislocations. Furthermore, these transformations were loading dependent and could be accommodated by GB junctions. This work provides atomistic insights into the dynamic structural transformation during GB migration. read less USED (low confidence) D. Scheiber, J. Svoboda, F. Fischer, H. Böhm, and L. Romaner, “Fully coupled segregation and precipitation kinetics model with ab initio input for the Fe-Au system,” Acta Materialia. 2022. link Times cited: 4 USED (low confidence) Q. Huang, Q.-E. Zhao, H. Zhou, and W. Yang, “Misorientation-dependent transition between grain boundary migration and sliding in FCC metals,” International Journal of Plasticity. 2022. link Times cited: 8 USED (low confidence) J. J. Wang, J. Gong, A. McGaughey, and D. Segal, “Simulations of heat transport in single-molecule junctions: Investigations of the thermal diode effect.,” The Journal of chemical physics. 2022. link Times cited: 4 Abstract: With the objective of understanding microscopic principles g… read moreAbstract: With the objective of understanding microscopic principles governing thermal energy flow in nanojunctions, we study phononic heat transport through metal-molecule-metal junctions using classical molecular dynamics (MD) simulations. Considering a single-molecule gold-alkanedithiol-gold junction, we first focus on aspects of method development and compare two techniques for calculating thermal conductance: (i) The Reverse Nonequilibrium MD (RNEMD) method, where heat is inputted and extracted at a constant rate from opposite metals. In this case, the thermal conductance is calculated from the nonequilibrium temperature profile that is created at the junction. (ii) The Approach-to-Equilibrium MD (AEMD) method, with the thermal conductance of the junction obtained from the equilibration dynamics of the metals. In both methods, simulations of alkane chains of a growing size display an approximate length-independence of the thermal conductance, with calculated values matching computational and experimental studies. The RNEMD and AEMD methods offer different insights, and we discuss their benefits and shortcomings. Assessing the potential application of molecular junctions as thermal diodes, alkane junctions are made spatially asymmetric by modifying their contact regions with the bulk, either by using distinct endgroups or by replacing one of the Au contacts with Ag. Anharmonicity is built into the system within the molecular force-field. We find that, while the temperature profile strongly varies (compared with the gold-alkanedithiol-gold junctions) due to these structural modifications, the thermal diode effect is inconsequential in these systems-unless one goes to very large thermal biases. This finding suggests that one should seek molecules with considerable internal anharmonic effects for developing nonlinear thermal devices. read less USED (low confidence) Q. Zhu et al., “Hierarchical twinning governed by defective twin boundary in metallic materials,” Science Advances. 2022. link Times cited: 24 Abstract: Dense networks of deformation twins endow metals and alloys … read moreAbstract: Dense networks of deformation twins endow metals and alloys with unprecedented mechanical properties. However, the formation mechanism of these hierarchical twin structures remains under debate, especially their relations with the imperfect nature of twin boundaries (TBs). Here, we investigate the intrinsic deformability of defective TBs in face-centered cubic metallic materials, where the inherent kinks on a set of primary TBs are demonstrated to facilitate the formation of secondary and hierarchical nanotwins. This defect-driven hierarchical twinning propensity is critically dependent on the kink height, which proves to be generally applicable in a variety of metals and alloys with low stacking fault energies. As a geometric extreme, a fivefold twin can be constructed via this self-activated hierarchical twinning mechanism. These findings differ from the conventional twinning mechanisms, enriching our understanding of twinning-mediated plasticity in metallic materials. read less USED (low confidence) S. R. Pulagam and A. Dutta, “Peierls–Nabarro modeling of twinning dislocations in fcc metals,” Computational Materials Science. 2022. link Times cited: 3 USED (low confidence) M. Khorrami, J. Mianroodi, and B. Svendsen, “Finite-deformation phase-field microelasticity with application to dislocation core and reaction modeling in fcc crystals,” Journal of the Mechanics and Physics of Solids. 2022. link Times cited: 2 USED (low confidence) Q. Zhu et al., “Atomistic dynamics of disconnection-mediated grain boundary plasticity: A case study of gold nanocrystals,” Journal of Materials Science & Technology. 2022. link Times cited: 3 USED (low confidence) S. Roy, S. Wille, D. Mordehai, and C. Volkert, “Investigating Nanoscale Contact Using AFM-Based Indentation and Molecular Dynamics Simulations,” Metals. 2022. link Times cited: 1 Abstract: In this work we study nanocontact plasticity in Au thin film… read moreAbstract: In this work we study nanocontact plasticity in Au thin films using an atomic force microscope based indentation method with the goal of relating the changes in surface morphology to the dislocations created by deformation. This provides a rigorous test of our understanding of deformation and dislocation mechanisms in small volumes. A series of indentation experiments with increasing maximum load was performed. Distinct elastic and plastic regimes were identified in the force-displacement curves, and the corresponding residual imprints were measured. Transmission electron microscope based measured dislocation densities appear to be smaller than the densities expected from the measured residual indents. With the help of molecular dynamics simulations we show that dislocation nucleation and glide alone fail to explain the low dislocation density. Increasing the temperature of the simulations accelerates the rate of thermally activated processes and promotes motion and annihilation of dislocations under the indent while transferring material to the upper surface; dislocation density decreases in the plastic zone and material piles up around the indent. Finally, we discuss why a significant number of cross-slip events is expected beneath the indent under experimental conditions and the implications of this for work hardening during wear. read less USED (low confidence) G. Zhou, Q. Huang, Y. Chen, X. Yu, and H. Zhou, “Annihilation Mechanism of Low-Angle Grain Boundary in Nanocrystalline Metals,” Metals. 2022. link Times cited: 3 Abstract: Due to the high density of grain boundaries (GBs), nanocryst… read moreAbstract: Due to the high density of grain boundaries (GBs), nanocrystalline metals possess superior properties, including enhanced strength, work hardening, and fatigue resistance, in comparison to their conventional counterparts. The expectation of GB migration is critical for grain coarsening and GB annihilation in these materials, significantly affecting the polycrystalline network and mechanical behavior. Here, we perform molecular dynamics (MD) simulations on gold (Au) nanocrystals containing multiple parallelly arranged GBs, with a focus on the investigation of annihilation mechanisms of low-angle grain boundaries (LAGBs). It is observed that the shear-coupled motion of LAGBs, consisting of dislocations, gives rise to their preliminary migration with the reduced separation distance between GBs. With subsequent GB motion, the LAGBs encountered with neighboring GBs, and can be annihilated by various mechanisms, including dislocations interpenetration, dislocations interaction, or dislocations absorption, depending on the specific configuration of the neighboring GB. These findings enhance our understanding of GB interactions and shed light on the controlled fabrication of high-performance nanocrystalline metals. read less USED (low confidence) S. Li et al., “eNanotwin assisted reversible formation of low angle grain boundary upon reciprocating shear load,” Acta Materialia. 2022. link Times cited: 7 USED (low confidence) Y. Chen et al., “A geometrical model for grain boundary migration mediated formation of multifold twins,” International Journal of Plasticity. 2022. link Times cited: 9 USED (low confidence) M. T. Curnan, D. Shin, W. Saidi, J. C. Yang, and J. Han, “Universally characterizing atomistic strain via simulation, statistics, and machine learning: low-angle grain boundaries,” Acta Materialia. 2022. link Times cited: 3 USED (low confidence) Y. Chen, Q. Huang, S. Zhao, H. Zhou, and J. Wang, “Interactions between Dislocations and Penta-Twins in Metallic Nanocrystals,” Metals. 2021. link Times cited: 1 Abstract: Dislocation interactions with twin boundary (TB) have been w… read moreAbstract: Dislocation interactions with twin boundary (TB) have been well-established in nanotwinned metals. Penta-twins, as an extreme of crystal twinning, are tacitly assumed to be more effective at blocking dislocation motions than conventional single or coplanar nanotwins. However, the mechanism underlying the interactions between dislocations and penta-twins remains largely unclear. Here, by combining in situ transmission electron microscope (TEM) nanomechanical testing and atomistic simulations, we rationalize the fundamental interactions between dislocations and penta-twins in Au nanocrystals. Our results reveal that the interactions between dislocations and penta-twins show some similar behaviors to the ones in the cases of coplanar nanotwins, including dislocation impedance at TBs, cross-slip into the twinning plane and transmission across the TB. In addition, penta-twins also exhibit some unique behaviors during dislocation interactions, including multiple cross-slip, dislocation-induced core dissociation and climb-induced annihilation/absorption at the penta-twin core. These findings enhance our mechanistic understanding of dislocation behaviors in penta-twins, shedding light on the accessible design of high-performance nanomaterials with multi-twinned nanostructures. read less USED (low confidence) A. Kedharnath, R. Kapoor, and A. Sarkar, “Classical molecular dynamics simulations of the deformation of metals under uniaxial monotonic loading: A review,” Computers & Structures. 2021. link Times cited: 16 USED (low confidence) Q. Zhu et al., “Revealing extreme twin-boundary shear deformability in metallic nanocrystals,” Science Advances. 2021. link Times cited: 40 Abstract: Twinned nanocrystals exhibit approximately 364% shear strain… read moreAbstract: Twinned nanocrystals exhibit approximately 364% shear strain via extensive twin boundary sliding. read less USED (low confidence) L. Fu et al., “Ultra-high strength yet superplasticity in a hetero-grain-sized nanocrystalline Au nanowire,” Journal of Materials Science & Technology. 2021. link Times cited: 8 USED (low confidence) W. Albrecht et al., “3D Atomic‐Scale Dynamics of Laser‐Light‐Induced Restructuring of Nanoparticles Unraveled by Electron Tomography,” Advanced Materials. 2021. link Times cited: 8 Abstract: Understanding light–matter interactions in nanomaterials is … read moreAbstract: Understanding light–matter interactions in nanomaterials is crucial for optoelectronic, photonic, and plasmonic applications. Specifically, metal nanoparticles (NPs) strongly interact with light and can undergo shape transformations, fragmentation and ablation upon (pulsed) laser excitation. Despite being vital for technological applications, experimental insight into the underlying atomistic processes is still lacking due to the complexity of such measurements. Herein, atomic resolution electron tomography is performed on the same mesoporous‐silica‐coated gold nanorod, before and after femtosecond laser irradiation, to assess the missing information. Combined with molecular dynamics (MD) simulations based on the experimentally determined 3D atomic‐scale morphology, the complex atomistic rearrangements, causing shape deformations and defect generation, are unraveled. These rearrangements are simultaneously driven by surface diffusion, facet restructuring, and strain formation, and are influenced by subtleties in the atomic distribution at the surface. read less USED (low confidence) S. Mathesan and D. Mordehai, “On the yielding and densification of nanoporous Au nanopillars in molecular dynamics simulations,” Computational Materials Science. 2021. link Times cited: 2 USED (low confidence) D. Holec, L. Löfler, G. Zickler, D. Vollath, and F. Fischer, “Surface stress of gold nanoparticles revisited,” International Journal of Solids and Structures. 2021. link Times cited: 6 USED (low confidence) M. T. Curnan, W. Saidi, J. C. Yang, and J. Han, “Universal prediction of strain footprints via simulation, statistics, and machine learning: low-Σ grain boundaries,” Acta Materialia. 2021. link Times cited: 4 USED (low confidence) Y. Chen et al., “Coordinated grain boundary deformation governed nanograin annihilation in shear cycling,” Journal of Materials Science & Technology. 2021. link Times cited: 5 USED (low confidence) Y. Cui, Y. Toku, Y. Kimura, and Y. Ju, “The deformation mechanism in cold-welded gold nanowires due to dislocation emission,” Computational Materials Science. 2021. link Times cited: 4 USED (low confidence) H. Böhm, G. Zickler, F. Fischer, and J. Svoboda, “Role of elastic strain energy in spheroidal precipitates revisited,” Mechanics of Materials. 2021. link Times cited: 5 USED (low confidence) S. Rahmati, R. Veiga, B. Jodoin, and A. Zúñiga, “Crystal orientation and grain boundary effects on plastic deformation of FCC particles under high velocity impacts,” Materialia. 2021. link Times cited: 11 USED (low confidence) C. Wang et al., “Three-Dimensional Atomic Structure of Grain Boundaries Resolved by Atomic-Resolution Electron Tomography.” 2020. link Times cited: 27 USED (low confidence) Y. Cui, Y. Toku, Y. Kimura, and Y. Ju, “True origin of the size effect in cold-welded metallic nanocrystals,” International Journal of Mechanical Sciences. 2020. link Times cited: 5 USED (low confidence) Q. Zhu et al., “In situ atomistic observation of grain boundary migration subjected to defect interaction,” Acta Materialia. 2020. link Times cited: 40 USED (low confidence) J. Sun et al., “Shrinking tension-compression asymmetry of Au nanowires by designed nanotwin boundaries,” Materials Chemistry and Physics. 2020. link Times cited: 1 USED (low confidence) L. Cao, Z. Zeng, and F. Fan, “Effect of lattice defects on the plastic Poisson’s ratio of nanoporous gold,” Scripta Materialia. 2020. link Times cited: 2 USED (low confidence) F. Valencia, M. Ramírez, A. Varas, and J. Rogan, “Understanding the Stability of Hollow Nanoparticles with Polycrystalline Shells,” Journal of Physical Chemistry C. 2020. link Times cited: 7 Abstract: The existence of polycrystalline shells has been widely repo… read moreAbstract: The existence of polycrystalline shells has been widely reported in the synthesis of hollow nanoparticles; however, the exact role displayed by the grain boundaries on the stability has been scarce... read less USED (low confidence) S. Mathesan and D. Mordehai, “Size-dependent elastic modulus of nanoporous Au nanopillars,” Acta Materialia. 2020. link Times cited: 14 USED (low confidence) L. Yang, J. Bian, W. Yuan, and G. Wang, “Statistical Characterization of the Yield Stress of Nanoparticles,” Acta Mechanica Solida Sinica. 2019. link Times cited: 0 USED (low confidence) R. Essajai, I. Tabtab, A. Mzerd, O. Mounkachi, N. Hassanain, and M. Qjani, “Molecular dynamics study of thermal properties of nanofluids composed of one-dimensional (1-D) network of interconnected gold nanoparticles,” Results in physics. 2019. link Times cited: 16 USED (low confidence) R. Essajai, A. Mzerd, N. Hassanain, and M. Qjani, “Thermal conductivity enhancement of nanofluids composed of rod-shaped gold nanoparticles: Insights from molecular dynamics,” Journal of Molecular Liquids. 2019. link Times cited: 36 USED (low confidence) L. Hao et al., “Mechanical behavior of metallic nanowires with twin boundaries parallel to loading axis,” Computational Materials Science. 2019. link Times cited: 5 USED (low confidence) R. Essajai, A. Rachadi, M. Qjani, A. Mzerd, and N. Hassanain, “Structural properties in single-component metallic nanoparticle: Insights from the simulation study,” Chemical Physics. 2019. link Times cited: 4 USED (low confidence) S. Roy, R. Gatti, B. Devincre, and D. Mordehai, “A multiscale study of the size-effect in nanoindentation of Au nanoparticles,” Computational Materials Science. 2019. link Times cited: 13 USED (low confidence) S. M. H. Lavasani, H. N. Pishkenari, and A. Meghdari, “How Chassis Structure and Substrate Crystalline Direction Affect the Mobility of Thermally Driven p-Carborane-Wheeled Nanocars,” The Journal of Physical Chemistry C. 2019. link Times cited: 14 Abstract: In recent years, various nanocars have been synthesized in o… read moreAbstract: In recent years, various nanocars have been synthesized in order to provide controlled mechanical function, transport other nanoparticles, or enable bottom-up assembly capability. There have even been racing competitions among well-known nanocars in which the wheels play an influential role. In this paper, the motion of thermally driven nanocars equipped with p-carborane wheels on Au(111) and Au(001) substrates is investigated. For the sake of comparison, classical all-atom molecular dynamics (MD) and rigid-body MD (RBMD) have been used to study the motion threshold as well as to analyze the effect of temperature, substrate crystalline direction, and chassis shape on the diffusive motion of a nanocooper, trimer, nanocaterpillar, and angled nanocar. It was observed that the motion regime of the nanocars on a gold substrate is a function of temperature and translational diffusion as well as the rotational diffusion coefficient, which shows non-Arrhenius behavior. Nanocar motion has three main regimes, trapp... read less USED (low confidence) A. R. Hinkle, W. Nöhring, R. J. Leute, T. Junge, and L. Pastewka, “The emergence of small-scale self-affine surface roughness from deformation,” Science Advances. 2019. link Times cited: 47 Abstract: When solids are deformed plastically, they develop surface r… read moreAbstract: When solids are deformed plastically, they develop surface roughness because plastic flow is not laminar at small scales. Most natural and man-made surfaces appear to be rough on many length scales. There is presently no unifying theory of the origin of roughness or the self-affine nature of surface topography. One likely contributor to the formation of roughness is deformation, which underlies many processes that shape surfaces such as machining, fracture, and wear. Using molecular dynamics, we simulate the biaxial compression of single-crystal Au, the high-entropy alloy Ni36.67Co30Fe16.67Ti16.67, and amorphous Cu50Zr50 and show that even surfaces of homogeneous materials develop a self-affine structure. By characterizing subsurface deformation, we connect the self-affinity of the surface to the spatial correlation of deformation events occurring within the bulk and present scaling relations for the evolution of roughness with strain. These results open routes toward interpreting and engineering roughness profiles. read less USED (low confidence) R. Huang, Y. Wen, A. Voter, and D. Perez, “Direct observations of shape fluctuation in long-time atomistic simulations of metallic nanoclusters,” Physical Review Materials. 2018. link Times cited: 7 USED (low confidence) A. Chew and R. V. V. Lehn, “Effect of Core Morphology on the Structural Asymmetry of Alkanethiol Monolayer-Protected Gold Nanoparticles,” The Journal of Physical Chemistry C. 2018. link Times cited: 18 Abstract: Gold nanoparticles (GNPs) are versatile materials suitable f… read moreAbstract: Gold nanoparticles (GNPs) are versatile materials suitable for various biological applications due to their tunable surface properties, but structure–function relationships between specific GNP components and GNP behavior are largely lacking. In this work, atomistic molecular dynamics simulations were used to study the influence of gold core morphology, size, and ligand length on the structure of uniformly nonpolar alkanethiol monolayer-protected GNPs in water. By use of a generalized system preparation workflow, three gold core models were selected for this study: (1) a uniformly spherical hollow gold core, (2) a spherical gold core cut from a bulk gold lattice, and (3) a faceted gold core obtained from variance-constrained semigrand-canonical simulations. Independent of the gold core morphology, we found that long alkanethiol ligands exhibit increased ligand order and form quasi-crystalline domains, or bundles, in which ligands orient in the same direction, leading to asymmetric monolayer structures. Fa... read less USED (low confidence) H. N. Pishkenari, F. S. Yousefi, and A. Taghibakhshi, “Determination of surface properties and elastic constants of FCC metals: a comparison among different EAM potentials in thin film and bulk scale,” Materials Research Express. 2018. link Times cited: 22 Abstract: Three independent elastic constants C11, C12, and C44 were c… read moreAbstract: Three independent elastic constants C11, C12, and C44 were calculated and compared using available potentials of eight different metals with FCC crystal structure; Gold, Silver, Copper, Nickel, Platinum, Palladium, Aluminum and Lead. In order to calculate the elastic constants, the second derivative of the energy density of each system was calculated with respect to different directions of strains. Each set of the elastic constants of the metals in bulk scale was compared with experimental results, and the average relative error was for each was calculated and compared with other available potentials. Then, using the Voigt-Reuss-Hill method, approximated values for Young and shear moduli and Poisson’s ratio of the FCC metals in the bulk scale were found for each potential. Furthermore, to observe the surface effects on the metals in nanoscale, surface elastic constants of the thin films of the metals have been calculated. In the study of the thin films of materials in nanoscale, the number of surface atoms is considerable compared to all atoms of the object. This leads to an increase in the surface effects, which influence the elastic properties. By considering this fact and employing related definitions and equations, the properties of the thin films of the metals were calculated, and the surface effects for different crystallographic directions were compared. Subsequently, in some cases, comparisons among characteristics of the metals in the thin film and bulk material were made. read less USED (low confidence) R. Essajai, A. Rachadi, E. Feddi, and N. Hassanain, “MD simulation-based study on the thermodynamic, structural and liquid properties of gold nanostructures,” Materials Chemistry and Physics. 2018. link Times cited: 18 USED (low confidence) S. Starikov, N. Lopanitsyna, D. Smirnova, and S. Makarov, “Atomistic simulation of Si-Au melt crystallization with novel interatomic potential,” Computational Materials Science. 2018. link Times cited: 20 USED (low confidence) M. Alania et al., “How precise can atoms of a nanocluster be located in 3D using a tilt series of scanning transmission electron microscopy images?,” Ultramicroscopy. 2017. link Times cited: 5 USED (low confidence) Z. Yang, L. Zheng, and D. Hu, “Atomistic study of the in-plane mechanical properties and deformation behaviors of nanohoneycomb Au,” Computational Materials Science. 2017. link Times cited: 2 USED (low confidence) M. SamsonovVladimir, G. BembelAlexei, PopovIlya, A. VasilyevSergey, and TalyzinIgor, “Solid-state wetting at the nanoscale: molecular dynamics and surface diffusion approach,” Surface Innovations. 2017. link Times cited: 7 Abstract: The authors simulated spreading of solid copper (Cu) and gol… read moreAbstract: The authors simulated spreading of solid copper (Cu) and gold (Au) nanoparticles (5–7 nm size) on the (100) face of the same metal by using molecular dynamics. Then, the results obtained for the co... read less USED (low confidence) R. Rezaei and C. Deng, “Pseudoelasticity and shape memory effects in cylindrical FCC metal nanowires,” Acta Materialia. 2017. link Times cited: 24 USED (low confidence) E. Symianakis and A. Kucernak, “Embedded atom method interatomic potentials fitted upon density functional theory calculations for the simulation of binary Pt Ni nanoparticles,” Computational Materials Science. 2017. link Times cited: 4 USED (low confidence) S. Roy and D. Mordehai, “Annihilation of edge dislocation loops via climb during nanoindentation,” Acta Materialia. 2017. link Times cited: 22 USED (low confidence) R.-guang Xu, Y. Xiang, and Y. Leng, “Computational simulations of solvation force and squeezing out of dodecane chain molecules in an atomic force microscope.,” The Journal of chemical physics. 2017. link Times cited: 11 Abstract: Understanding the squeeze out behaviors of liquid films at n… read moreAbstract: Understanding the squeeze out behaviors of liquid films at nanometer scale in an atomic force microscope (AFM) has been a significant interest since the 1990s. We carry out all-atom static-mode AFM simulations in a liquid-vapor molecular dynamics ensemble to investigate the solvation force oscillation and squeeze out mechanisms of a confined linear dodecane fluid between a gold AFM tip and a mica substrate. Solvation force oscillations are found to be associated with the layering transition of the liquid film and unstable jumps of the AFM tip. Detailed structural analyses and molecular animations show that the local permeation of chain molecules and the squeeze out of molecules near the edge of contact promote the layering transition under compression. The confinement-induced slow down dynamics is manifested by the decrease in diffusivity and increase in rotational relaxation times. However, the persistent diffusive behavior of dodecane chain molecules even in the single-monolayer film is attributed to the chain sliding motions in the film due to the substantial vacancy space and thermal fluctuations. read less USED (low confidence) S. Namsani and J. Singh, “Dewetting dynamics of a gold film on graphene: implications for nanoparticle formation.,” Faraday discussions. 2016. link Times cited: 8 Abstract: The dynamics of dewetting of gold films on graphene surfaces… read moreAbstract: The dynamics of dewetting of gold films on graphene surfaces is investigated using molecular dynamics simulation. The effect of temperature (973-1533 K), film diameter (30-40 nm) and film thickness (0.5-3 nm) on the dewetting mechanism, leading to the formation of nanoparticles, is reported. The dewetting behavior for films ≤5 Å is in contrast to the behavior seen for thicker films. The retraction velocity, in the order of ∼300 m s(-1) for a 1 nm film, decreases with an increase in film thickness, whereas it increases with temperature. However at no point do nanoparticles detach from the surface within the temperature range considered in this work. We further investigated the self-assembly behavior of nanoparticles on graphene at different temperatures (673-1073 K). The process of self-assembly of gold nanoparticles is favorable at lower temperatures than at higher temperatures, based on the free-energy landscape analysis. Furthermore, the shape of an assembled structure is found to change from spherical to hexagonal, with a marked propensity towards an icosahedral structure based on the bond-orientational order parameters. read less USED (low confidence) R.-guang Xu and Y. Leng, “Contact stiffness and damping of liquid films in dynamic atomic force microscope.,” The Journal of chemical physics. 2015. link Times cited: 11 Abstract: The mechanical properties and dissipation behaviors of nanom… read moreAbstract: The mechanical properties and dissipation behaviors of nanometers confined liquid films have been long-standing interests in surface force measurements. The correlation between the contact stiffness and damping of the nanoconfined film is still not well understood. We establish a novel computational framework through molecular dynamics (MD) simulation for the first time to study small-amplitude dynamic atomic force microscopy (dynamic AFM) in a simple nonpolar liquid. Through introducing a tip driven dynamics to mimic the mechanical oscillations of the dynamic AFM tip-cantilever assembly, we find that the contact stiffness and damping of the confined film exhibit distinct oscillations within 6-7 monolayer distances, and they are generally out-of-phase. For the solid-like film with integer monolayer thickness, further compression of the film before layering transition leads to higher stiffness and lower damping, while much lower stiffness and higher damping occur at non-integer monolayer distances. These two alternating mechanisms dominate the mechanical properties and dissipation behaviors of simple liquid films under cyclic elastic compression and inelastic squeeze-out. Our MD simulations provide a direct picture of correlations between the structural property, mechanical stiffness, and dissipation behavior of the nanoconfined film. read less USED (low confidence) E. S. Wise, M. Liu, and T. Miller, “Sputtering of cubic metal crystals by low-energy xenon-ions,” Computational Materials Science. 2015. link Times cited: 5 USED (low confidence) Y. Shao, X. Yang, J. Li, and X. Zhao, “Strain Fields around Dislocation Cores Studied by Analyzing Coordinates of Discrete Atoms,” Materials Science Forum. 2015. link Times cited: 0 Abstract: Dislocation core structures in Au and Cu crystals are invest… read moreAbstract: Dislocation core structures in Au and Cu crystals are investigated by means of quasicontinuum simulations combined with the embedded atom method potentials. A dislocation pair in a graphene sheet, which is observed by Warner et al. experimentally, is also analyzed in the present work. The strain fields around these dislocations in Au, Cu, and graphene crystals are calculated by analyzing the coordinates of discrete atoms, which is a strain tensor calculation method proposed by Zimmerman et al., and compared with theoretical predictions based on Foreman dislocation model. It is shown that the strain fields given by Zimmerman theory are completely suitable for describing the dislocation core structures of Au, Cu and graphene crystals. However, compared with the results of Au and Cu, the Zimmerman strain field in the vicinity of graphene dislocation core is a little less accurate, possibly due to the effect of lattice symmetry of graphene, which needs to be clarified in the future study. read less USED (low confidence) R. Cao, Y. Deng, and C. Deng, “Ultrahigh plastic flow in Au nanotubes enabled by surface stress facilitated reconstruction,” Acta Materialia. 2015. link Times cited: 6 USED (low confidence) R. Aghababaei, G. Anciaux, and J. Molinari, “Impact of internal crystalline boundaries on lattice thermal conductivity: Importance of boundary structure and spacing,” Applied Physics Letters. 2014. link Times cited: 13 Abstract: The low thermal conductivity of nano-crystalline materials i… read moreAbstract: The low thermal conductivity of nano-crystalline materials is commonly explained via diffusive scattering of phonons by internal boundaries. In this study, we have quantitatively studied phonon-crystalline boundaries scattering and its effect on the overall lattice thermal conductivity of crystalline bodies. Various types of crystalline boundaries such as stacking faults, twins, and grain boundaries have been considered in FCC crystalline structures. Accordingly, the specularity coefficient has been determined for different boundaries as the probability of the specular scattering across boundaries. Our results show that in the presence of internal boundaries, the lattice thermal conductivity can be characterized by two parameters: (1) boundary spacing and (2) boundary excess free volume. We show that the inverse of the lattice thermal conductivity depends linearly on a non-dimensional quantity which is the ratio of boundary excess free volume over boundary spacing. This shows that phonon scattering across crystalline boundaries is mainly a geometrically favorable process rather than an energetic one. Using the kinetic theory of phonon transport, we present a simple analytical model which can be used to evaluate the lattice thermal conductivity of nano-crystalline materials where the ratio can be considered as an average density of excess free volume. While this study is focused on FCC crystalline materials, where inter-atomic potentials and corresponding defect structures have been well studied in the past, the results would be quantitatively applicable for semiconductors in which heat transport is mainly due to phonon transport. read less USED (low confidence) A. Maier, D. Mari, I. Tkalčec, and R. Schaller, “Theoretical modelling of grain boundary anelastic relaxations,” Acta Materialia. 2014. link Times cited: 17 USED (low confidence) Y. Zhou and K. Fichthorn, “Internal Stress-Induced Orthorhombic Phase in 5-Fold-Twinned Noble Metal Nanowires,” Journal of Physical Chemistry C. 2014. link Times cited: 28 Abstract: We use atomistic simulations to show that 5-fold-twinned nan… read moreAbstract: We use atomistic simulations to show that 5-fold-twinned nanowires of several face-centered cubic metals (Ag, Au, Cu, and Pd) exhibit an overall body-centered orthorhombic phase resulting from the large internal stress associated with their twinned structure. The distribution of atomic stress in the nanowires confirms the existence of a disclination at the 5-fold axis, in addition to an anisotropic distortion of the lattice. We find that two regions of the nanowire are highly stressed: local stress maxima are distributed in the shape of leaflets running along each twin boundary, as well as in semicircular regions near the free surfaces. The large elastic strain energy associated with the distortion may be partially released via the formation and propagation of partial dislocations, which are restricted to a single subunit of the nanowire. Our calculations are in line with experiment and indicate the complex ways in which the structures of these metal nanocrystals can depend on their shape. read less USED (low confidence) W. Tucker and P. Schelling, “Analysis of simulation methodology for calculation of the heat of transport for vacancy thermodiffusion,” Journal of Applied Physics. 2014. link Times cited: 6 Abstract: Computation of the heat of transport Qa* in monatomic crysta… read moreAbstract: Computation of the heat of transport Qa* in monatomic crystalline solids is investigated using the methodology first developed by Gillan [J. Phys. C: Solid State Phys. 11, 4469 (1978)] and further developed by Grout and coworkers [Philos. Mag. Lett. 74, 217 (1996)], referred to as the Grout-Gillan method. In the case of pair potentials, the hopping of a vacancy results in a heat wave that persists for up to 10 ps, consistent with previous studies. This leads to generally positive values for Qa* which can be quite large and are strongly dependent on the specific details of the pair potential. By contrast, when the interactions are described using the embedded atom model, there is no evidence of a heat wave, and Qa* is found to be negative. This demonstrates that the dynamics of vacancy hopping depends strongly on the details of the empirical potential. However, the results obtained here are in strong disagreement with experiment. Arguments are presented which demonstrate that there is a fundamental error m... read less USED (low confidence) R.-guang Xu and Y. Leng, “Solvation force simulations in atomic force microscopy.,” The Journal of chemical physics. 2014. link Times cited: 15 Abstract: Solvation force oscillation in octamethylcyclotetrasiloxane … read moreAbstract: Solvation force oscillation in octamethylcyclotetrasiloxane (OMCTS) versus the distance between an atomic force microscope (AFM) tip and mica substrate has been studied through molecular dynamics simulations. A driving spring model in a liquid-vapor molecular ensemble is used to explore the force oscillation mechanism. It has been found that OMCTS fluid in tip-substrate contact has a strong tendency to form a layered structure, starting from n = 8 layers. The force profile obtained from simulation is qualitatively similar to those in contact mode AFM experiments. However, the bulk-like diffusion and rotation of OMCTS molecules underneath the AFM tip suggest that, under the tip-substrate confinement geometry, the layered OMCTS film cannot form a solidified structure except under n = 2 extreme contact-layer confinement. read less USED (low confidence) H. Xie, T. Yu, and F. Yin, “Tension–compression asymmetry in homogeneous dislocation nucleation stress of single crystals Cu, Au, Ni and Ni3Al,” Materials Science and Engineering A-structural Materials Properties Microstructure and Processing. 2014. link Times cited: 29 USED (low confidence) E. Wood et al., “Size effects in bimetallic nickel–gold nanowires: Insight from atomic force microscopy nanoindentation,” Acta Materialia. 2014. link Times cited: 12 USED (low confidence) M. Sun, F. Xiao, and C. Deng, “Near-ideal strength in metal nanotubes revealed by atomistic simulations,” Applied Physics Letters. 2013. link Times cited: 10 Abstract: Here we report extraordinary mechanical properties revealed … read moreAbstract: Here we report extraordinary mechanical properties revealed by atomistic simulations in metal nanotubes with hollow interior that have been long overlooked. Particularly, the yield strength in [1 1 1] Au nanotubes is found to be up to 60% higher than the corresponding solid Au nanowire, which approaches the theoretical ideal strength in Au. Furthermore, a remarkable transition from sharp to smooth yielding is observed in Au nanotubes with decreasing wall thickness. The ultrahigh tensile strength in [1 1 1] Au nanotube might originate from the repulsive image force exerted by the interior surface against dislocation nucleation from the outer surface. read less USED (low confidence) M. A. Karolewski, R. Cavell, R. Gordon, C. Glover, M. Cheah, and M. Ridgway, “Predicting XAFS scattering path cumulants and XAFS spectra for metals (Cu, Ni, Fe, Ti, Au) using molecular dynamics simulations.,” Journal of synchrotron radiation. 2013. link Times cited: 5 Abstract: The ability of molecular dynamics (MD) simulations to suppor… read moreAbstract: The ability of molecular dynamics (MD) simulations to support the analysis of X-ray absorption fine-structure (XAFS) data for metals is evaluated. The low-order cumulants (ΔR, σ(2), C3) for XAFS scattering paths are calculated for the metals Cu, Ni, Fe, Ti and Au at 300 K using 28 interatomic potentials of the embedded-atom method type. The MD cumulant predictions were evaluated within a cumulant expansion XAFS fitting model, using global (path-independent) scaling factors. Direct simulations of the corresponding XAFS spectra, χ(R), are also performed using MD configurational data in combination with the FEFF ab initio code. The cumulant scaling parameters compensate for differences between the real and effective scattering path distributions, and for any errors that might exist in the MD predictions and in the experimental data. The fitted value of ΔR is susceptible to experimental errors and inadvertent lattice thermal expansion in the simulation crystallites. The unadjusted predictions of σ(2) vary in accuracy, but do not show a consistent bias for any metal except Au, for which all potentials overestimate σ(2). The unadjusted C3 predictions produced by different potentials display only order-of-magnitude consistency. The accuracy of direct simulations of χ(R) for a given metal varies among the different potentials. For each of the metals Cu, Ni, Fe and Ti, one or more of the tested potentials was found to provide a reasonable simulation of χ(R). However, none of the potentials tested for Au was sufficiently accurate for this purpose. read less USED (low confidence) G. Grochola, I. Snook, and S. Russo, “Static substrate deposition: Toward longer time scale deposition simulations,” Physical Review B. 2011. link Times cited: 6 Abstract: We report on the development of a new method for simulating … read moreAbstract: We report on the development of a new method for simulating the deposition of atoms onto surfaces, which allows for longer time scales and/or larger system sizes. The method involves simulating only the deposited material on a purely static substrate and corrects for the missing thermal fluctuations and energy exchange effects that surface atoms experience as a result of a static substrate. This method may be viewed as an intermediate approximation between the discrete kinetic Monte Carlo and the full molecular dynamics (MD) methods, because it retains the full trajectory dynamics for the deposited atoms. The method can achieve speed-up times of approximately two orders of magnitude for submonolayer depositions on large simulation substrates. We first apply the method to an ideal prototypical system involving the deposition of Pt material on Pt substrates with two-dimensional Ag monolayer substrate patterns, where we show that it produces nanostructures and small cluster diffusion behavior almost identical to that observed during full MD simulations. As an ideal second application of the method, we use it to deposit Pt and Au onto a reconstructed Au(111) surface representative of a herringbone reconstruction and comment on the findings. Finally, we comment on the limitations and possible future improvements. read less USED (low confidence) D. Mordehai, S. Lee, B. Backes, D. Srolovitz, W. Nix, and E. Rabkin, “Size effect in compression of single-crystal gold microparticles,” Acta Materialia. 2011. link Times cited: 140 USED (low confidence) X. Guo and Y. Xia, “Repulsive force vs. source number: Competing mechanisms in the yield of twinned gold nanowires of finite length,” Acta Materialia. 2011. link Times cited: 40 USED (low confidence) D. Mordehai, M. Kazakevich, D. Srolovitz, and E. Rabkin, “Nanoindentation size effect in single-crystal nanoparticles and thin films: A comparative experimental and simulation study,” Acta Materialia. 2011. link Times cited: 98 USED (low confidence) P. Zoontjens, G. Grochola, I. Snook, and S. Russo, “A kinetic Monte Carlo study of Pt on Au(111) with applications to bimetallic catalysis,” Journal of Physics: Condensed Matter. 2011. link Times cited: 6 Abstract: Pt-decorated Au nanostructures and bimetallic PtAu nanoparti… read moreAbstract: Pt-decorated Au nanostructures and bimetallic PtAu nanoparticles have been shown to act as catalysts. Consequently we investigate the formation of extended Pt decorations of an Au island edge on Au(111) as possible catalysts. The investigation is by simulation using the kinetic Monte Carlo method. The effects of varying the rate of deposition of Pt atoms and the simulation temperature on the morphology of the resulting Pt nanostructures were investigated. The thickness and roughness of the nanostructures are readily influenced, with temperature being the more important factor. A combination of both high temperature and low deposition rate was the most effective at reducing the roughness. PtAu alloying in the Au island edge was identified. This work is (to the best of our knowledge) the first kinetic Monte Carlo simulation study of the formation of Pt nanostructures on Au. We demonstrate how the morphology of the Pt nanostructures can be controlled. The nanostructures studied here, comprising an adjustable mix of Pt overlayers and novel 1D PtAu surface alloys, are expected to be of considerable interest as potential bimetallic nano-catalysts. read less USED (low confidence) H. Zheng et al., “Discrete plasticity in sub-10-nm-sized gold crystals,” Nature Communications. 2010. link Times cited: 288 USED (low confidence) E. Rabkin, H. Nam, and D. Srolovitz, “Atomistic simulation of the deformation of gold nanopillars,” Acta Materialia. 2007. link Times cited: 110 USED (low confidence) L. Klinger and E. Rabkin, “Thermal and Mechanical Stability of Polycrystalline Nanowires,” Defect and Diffusion Forum. 2007. link Times cited: 0 Abstract: We considered a polycrystalline cylindrical nanowire with ba… read moreAbstract: We considered a polycrystalline cylindrical nanowire with bamboo microstructure strained uniaxially by an external load. Our molecular dynamic computer simulations demonstrated that grain boundary grooving plays an important role in determining the morphological stability of nanowires. Also, an exceptionally high yield stress of nanowires emphasizes the importance of diffusion in their plastic deformation under applied load. We formulated a phenomenological diffusion-based model describing morphological stability and diffusion-controlled deformation behaviour of polycrystalline nanowires. The kinetics of the shape changes was calculated numerically. read less USED (low confidence) Y. Gan and Z. Sun, “Crystal structure dependence of the breathing vibration of individual gold nanodisks induced by the ultrafast laser.,” Applied optics. 2019. link Times cited: 3 Abstract: The ultrafast laser-excited breathing vibrations of gold nan… read moreAbstract: The ultrafast laser-excited breathing vibrations of gold nanodisks with different crystal structures have been studied via atomistic simulations. The vibrational periods and damping rates of nanodisks are obtained by the analysis of the simulated transient responses of nanodisks. It is shown that the breathing period of nanodisks is considerably dependent on their crystal structure, which is contrary to the cases for the breathing vibration of metal nanospheres and nanorods. Furthermore, single-crystal nanodisks exhibit much lower intrinsic damping as compared with polycrystalline nanodisks, for which the additional energy dissipation by the grain boundaries in the polycrystalline nanodisks could be one major factor. read less USED (low confidence) E. Rothchild, Q. J. Li, and E. Ma, “On the validity of using the Debye model to quantitatively correlate the shear modulus with vibrational properties in cubic metals,” Scripta Materialia. 2019. link Times cited: 1 USED (low confidence) D. Holec, L. Löfler, G. Zickler, D. Vollath, and F. Fischer, “Surface Stress of Metallic Nanoparticles Revisited,” Chemical Engineering (Engineering) eJournal. 2019. link Times cited: 0 Abstract: The surface energy has been one of the topics of atomistic r… read moreAbstract: The surface energy has been one of the topics of atomistic research for nanoparticles in the last decades. However, the physical role of surface stress and its quantification have been a lot less an object of research. Assumptions for the surface stress, going back to the thermodynamic basis of continua, have been popular. As an example the surface stress (state) follows as derivatives of the surface energy with a rather "classical" evolution equation for the deformation energy. The current concept introduces a combination of atomistic modelling and continuum mechanics for a core-shell system. Considering crystalline gold nanoparticles with radii in the range of 1nm to 9 nm, a unique equation can be derived for the surface stress. read less NOT USED (low confidence) Q.-E. Zhao et al., “Imaging of atomic stress at grain boundaries based on machine learning,” Journal of the Mechanics and Physics of Solids. 2023. link Times cited: 0 NOT USED (low confidence) K. Fichthorn, “Theory of Anisotropic Metal Nanostructures.,” Chemical reviews. 2023. link Times cited: 5 Abstract: A significant challenge in the development of functional mat… read moreAbstract: A significant challenge in the development of functional materials is understanding the growth and transformations of anisotropic colloidal metal nanocrystals. Theory and simulations can aid in the development and understanding of anisotropic nanocrystal syntheses. The focus of this review is on how results from first-principles calculations and classical techniques, such as Monte Carlo and molecular dynamics simulations, have been integrated into multiscale theoretical predictions useful in understanding shape-selective nanocrystal syntheses. Also, examples are discussed in which machine learning has been useful in this field. There are many areas at the frontier in condensed matter theory and simulation that are or could be beneficial in this area and these prospects for future progress are discussed. read less NOT USED (low confidence) Q. Pei, J. Guo, A. Suwardi, and G. Zhang, “Insights into interfacial thermal conductance in Bi2Te3-based systems for thermoelectrics,” Materials Today Physics. 2023. link Times cited: 5 NOT USED (low confidence) A. Hegde, E. Weiss, W. Windl, H. Najm, and C. Safta, “Bayesian calibration of interatomic potentials for binary alloys,” Computational Materials Science. 2022. link Times cited: 1 NOT USED (low confidence) P. Kang et al., “Nanoparticle Fragmentation Below the Melting Point Under Single Picosecond Laser Pulse Stimulation.,” The journal of physical chemistry. C, Nanomaterials and interfaces. 2021. link Times cited: 4 Abstract: Understanding the laser-nanomaterials interaction including … read moreAbstract: Understanding the laser-nanomaterials interaction including nanomaterial fragmentation has important implications in nanoparticle manufacturing, energy, and biomedical sciences. So far, three mechanisms of laser-induced fragmentation have been recognized including non-thermal processes and thermomechanical force under femtosecond pulses, and the phase transitions under nanosecond pulses. Here we show that single picosecond (ps) laser pulse stimulation leads to anomalous fragmentation of gold nanoparticles that deviates from these three mechanisms. The ps laser fragmentation was weakly dependent on particle size, and it resulted in a bimodal size distribution. Importantly, ps laser stimulation fragmented particles below the whole particle melting point and below the threshold for non-thermal mechanism. We propose a framework based on near-field enhancement and nanoparticle surface melting to account for the ps laser-induced fragmentation observed here. This study reveals a new form of surface ablation that occurs under picosecond laser stimulation at low fluence. read less NOT USED (low confidence) J. Chapman and R. Ramprasad, “Nanoscale Modeling of Surface Phenomena in Aluminum Using Machine Learning Force Fields,” The Journal of Physical Chemistry C. 2020. link Times cited: 7 Abstract: The study of nano-scale surface phenomena is essential in un… read moreAbstract: The study of nano-scale surface phenomena is essential in understanding the physical processes that aid in technologically relevant applications, such as catalysis, material growth, and failure nuc... read less NOT USED (low confidence) J. Chapman, R. Batra, and R. Ramprasad, “Machine learning models for the prediction of energy, forces, and stresses for Platinum,” Computational Materials Science. 2020. link Times cited: 18 NOT USED (low confidence) X. Hu, Q. Yang, T. Ye, and A. Martini, “Simulation of Sub-nanometer Contrast in Dynamic Atomic Force Microscopy of Hydrophilic Alkanethiol Self-assembled Monolayers in Water.,” Langmuir : the ACS journal of surfaces and colloids. 2020. link Times cited: 4 Abstract: Atomic resolution imaging of surfaces in liquid environments… read moreAbstract: Atomic resolution imaging of surfaces in liquid environments using atomic force microscopy is challenging both in terms of reproducibility and measurement interpretation. To understand the origins of these challenges, we used molecular dynamics simulations of atomic force microscopy (AFM) on hydrophilic self-assembled monolayers (SAM) in water. The force on the model AFM tip was calculated as a function of lateral and vertical position relative to the SAM surface. The contributions of the water and SAMs to the overall force were analyzed and the former was correlated to the water density distribution. Then, dynamic AFM was modeled by oscillating the tip at a driving amplitude. It was found that the contrast between amplitudes at different lateral positions on the surface was dependent on the vertical position of the tip. Lastly, amplitude maps were produced for two vertical positions at constant height and the ability to capture atomic resolution was related to the force on the tip. These results offer an explanation for observed instability in atomic scale imaging using AFM and more generally provide insight into the contrast mechanisms of surface images obtained in liquid environments. read less NOT USED (low confidence) J. Wang, G. Cao, Z. Zhang, and F. Sansoz, “Size-dependent dislocation-twin interactions.,” Nanoscale. 2019. link Times cited: 24 Abstract: Dislocation-twin interactions critically control the plastic… read moreAbstract: Dislocation-twin interactions critically control the plastic deformation and ultrahigh strength of nanotwinned metals. Here, we report a strong twin-thickness dependence of dislocation-twin interaction mechanisms from the tensile deformation of face-centered cubic metallic nanocrystals by in situ nanomechanical testing. Direct observations at atomic scale reveal that the predominant dislocation-twin interaction abruptly changes from dislocation transmission on the {111} slip planes to the unusual (100) slip plane of the twin, when the twin thickness is smaller than 4 layers. Using atomistic simulations, we find that the energy barrier for {100} slip transmission mechanism gradually decreases, with decreasing twin thickness, below the energy level required for normal (111) slip transmission, which remains identical for all twin sizes. Our in situ observations and simulations provide atomistic insights into a fundamentally new mechanism of plasticity in nanotwinned metals, down to the lowest twin size limit. read less NOT USED (low confidence) K. Choudhary, A. Biacchi, S. Ghosh, L. Hale, A. Walker, and F. Tavazza, “High-throughput assessment of vacancy formation and surface energies of materials using classical force-fields,” Journal of Physics: Condensed Matter. 2018. link Times cited: 16 Abstract: In this work, we present an open access database for surface… read moreAbstract: In this work, we present an open access database for surface and vacancy-formation energies using classical force-fields (FFs). These quantities are essential in understanding diffusion behavior, nanoparticle formation and catalytic activities. FFs are often designed for a specific application, hence, this database allows the user to understand whether a FF is suitable for investigating particular defect and surface-related material properties. The FF results are compared to density functional theory and experimental data whenever applicable for validation. At present, we have 17 506 surface energies and 1000 vacancy formation energies calculation in our database and the database is still growing. All the data generated, and the computational tools used, are shared publicly at the following websites: www.ctcms.nist.gov/~knc6/periodic.html, https://jarvis.nist.gov and https://github.com/usnistgov/jarvis. Approximations used during the high-throughput calculations are clearly mentioned. Using some of the example cases, we show how our data can be used to directly compare different FFs for a material and to interpret experimental findings such as using Wulff construction for predicting equilibrium shape of nanoparticles. Similarly, the vacancy formation energies data can be useful in understanding diffusion related properties. read less NOT USED (low confidence) R. J. Rees and M. Spencer, “The science and life of Ian K. Snook,” Molecular Simulation. 2016. link Times cited: 0 Abstract: In your life, you are fortunate indeed to be able to count a… read moreAbstract: In your life, you are fortunate indeed to be able to count a close friend as someone who has been your teacher and mentor; Ian Snook was such a friend. He was a talented and internationally recognized scientist, lecturer and research advisor; it was however, Ian’s generosity, humour and above all his humility that those of us privileged to know him most admired. In every sense, Ian was a lateral and innovative thinker. He had considerable and adaptable skills in pure and applied mathematics, which he employed often and with great success in both developing computational methods and condensed matter theory. One only need read his monograph on the application of the Langevin and Generalised Langevin equations to the dynamics of atomic and complex fluids to recognise his mathematical prowess. His skill in recognizing geometrical patterns and resolving them through innovative mathematical methods enabled him to tackle many difficult problems in the area of colloid physics (in the early years) through to nanoscience (more recently). We will not attempt here to describe in detail Ian’s life but will refer the reader to a website dedicated to him iansnook.com read less NOT USED (low confidence) Y. Feruz and D. Mordehai, “Towards a universal size-dependent strength of face-centered cubic nanoparticles,” Acta Materialia. 2016. link Times cited: 37 NOT USED (low confidence) Z. Trautt, F. Tavazza, and C. Becker, “Facilitating the selection and creation of accurate interatomic potentials with robust tools and characterization,” Modelling and Simulation in Materials Science and Engineering. 2015. link Times cited: 14 Abstract: The Materials Genome Initiative seeks to significantly decre… read moreAbstract: The Materials Genome Initiative seeks to significantly decrease the cost and time of development and integration of new materials. Within the domain of atomistic simulations, several roadblocks stand in the way of reaching this goal. While the NIST Interatomic Potentials Repository hosts numerous interatomic potentials (force fields), researchers cannot immediately determine the best choice(s) for their use case. Researchers developing new potentials, specifically those in restricted environments, lack a comprehensive portfolio of efficient tools capable of calculating and archiving the properties of their potentials. This paper elucidates one solution to these problems, which uses Python-based scripts that are suitable for rapid property evaluation and human knowledge transfer. Calculation results are visible on the repository website, which reduces the time required to select an interatomic potential for a specific use case. Furthermore, property evaluation scripts are being integrated with modern platforms to improve discoverability and access of materials property data. To demonstrate these scripts and features, we will discuss the automation of stacking fault energy calculations and their application to additional elements. While the calculation methodology was developed previously, we are using it here as a case study in simulation automation and property calculations. We demonstrate how the use of Python scripts allows for rapid calculation in a more easily managed way where the calculations can be modified, and the results presented in user-friendly and concise ways. Additionally, the methods can be incorporated into other efforts, such as openKIM. read less NOT USED (low confidence) K. Zhang, M. Fan, Y. Liu, J. Schroers, M. Shattuck, and C. O’Hern, “Beyond packing of hard spheres: The effects of core softness, non-additivity, intermediate-range repulsion, and many-body interactions on the glass-forming ability of bulk metallic glasses.,” The Journal of chemical physics. 2015. link Times cited: 16 Abstract: When a liquid is cooled well below its melting temperature a… read moreAbstract: When a liquid is cooled well below its melting temperature at a rate that exceeds the critical cooling rate Rc, the crystalline state is bypassed and a metastable, amorphous glassy state forms instead. Rc (or the corresponding critical casting thickness dc) characterizes the glass-forming ability (GFA) of each material. While silica is an excellent glass-former with small Rc < 10(-2) K/s, pure metals and most alloys are typically poor glass-formers with large Rc > 10(10) K/s. Only in the past thirty years have bulk metallic glasses (BMGs) been identified with Rc approaching that for silica. Recent simulations have shown that simple, hard-sphere models are able to identify the atomic size ratio and number fraction regime where BMGs exist with critical cooling rates more than 13 orders of magnitude smaller than those for pure metals. However, there are a number of other features of interatomic potentials beyond hard-core interactions. How do these other features affect the glass-forming ability of BMGs? In this manuscript, we perform molecular dynamics simulations to determine how variations in the softness and non-additivity of the repulsive core and form of the interatomic pair potential at intermediate distances affect the GFA of binary alloys. These variations in the interatomic pair potential allow us to introduce geometric frustration and change the crystal phases that compete with glass formation. We also investigate the effect of tuning the strength of the many-body interactions from zero to the full embedded atom model on the GFA for pure metals. We then employ the full embedded atom model for binary BMGs and show that hard-core interactions play the dominant role in setting the GFA of alloys, while other features of the interatomic potential only change the GFA by one to two orders of magnitude. Despite their perturbative effect, understanding the detailed form of the intermetallic potential is important for designing BMGs with cm or greater casting thickness. read less NOT USED (low confidence) W. Paul, D. Oliver, and P. Grütter, “Indentation-formed nanocontacts: an atomic-scale perspective.,” Physical chemistry chemical physics : PCCP. 2014. link Times cited: 15 Abstract: One-to-one comparisons between indentation experiments and a… read moreAbstract: One-to-one comparisons between indentation experiments and atomistic modelling have until recently been hampered by the discrepancy in length scales of the two approaches. Here, we review progress in atomic-scale nanoindentation experiments employing scanning probe techniques to achieve depth-sensing indentation and field ion microscopy to permit detailed indenter characterization. This perspective addresses both mechanical (dislocation nucleation, defect structures, adhesion, indenter effects) and electronic (interface, disorder, and vacancy scattering) properties of indentation-formed contacts. read less NOT USED (low confidence) W. Ong, S. Majumdar, J. Malen, and A. McGaughey, “Coupling of Organic and Inorganic Vibrational States and Their Thermal Transport in Nanocrystal Arrays,” Journal of Physical Chemistry C. 2014. link Times cited: 67 Abstract: Through atomistic computational analysis of thermal transpor… read moreAbstract: Through atomistic computational analysis of thermal transport in nanocrystal arrays (NCAs), we find that vibrational states couple elastically across the organic–inorganic interfaces with a resulting flux that depends on the ligand grafting density and the overlap between the core and ligand vibrational spectra. The modeling was performed using molecular dynamics simulations and lattice dynamics calculations on a gold-dodecanethiol NCA built using a robust self-assembly methodology. Our approach is validated by comparing the predicted NCA thermal conductivities against experimental measurements [Ong et al. Nat. Mater. 2013, 12, 410], with agreement found in both magnitude and trends. The self-assembly methodology enables prediction of general NCA behavior and detailed probing of experimentally inaccessible nanoscale phenomena. read less NOT USED (low confidence) J. Wang et al., “Near-ideal theoretical strength in gold nanowires containing angstrom scale twins,” Nature Communications. 2013. link Times cited: 229 NOT USED (low confidence) J. Han, L. Fang, J. Sun, Y. Han, and K. Sun, “Length-dependent mechanical properties of gold nanowires.,” Journal of applied physics. 2012. link Times cited: 31 Abstract: The well-known "size effect" is not only related t… read moreAbstract: The well-known "size effect" is not only related to the diameter but also to the length of the small volume materials. It is unfortunate that the length effect on the mechanical behavior of nanowires is rarely explored in contrast to the intensive studies of the diameter effect. The present paper pays attention to the length-dependent mechanical properties of 〈111〉-oriented single crystal gold nanowires employing the large-scale molecular dynamics simulation. It is discovered that the ultrashort Au nanowires exhibit a new deformation and failure regime-high elongation and high strength. The constrained dislocation nucleation and transient dislocation slipping are observed as the dominant mechanism for such unique combination of high strength and high elongation. A mechanical model based on image force theory is developed to provide an insight to dislocation nucleation and capture the yield strength and nucleation site of first partial dislocation indicated by simulation results. Increasing the length of the nanowires, the ductile-to-brittle transition is confirmed. And the new explanation is suggested in the predict model of this transition. Inspired by the superior properties, a new approach to strengthen and toughen nanowires-hard/soft/hard sandwich structured nanowires is suggested. A preliminary evidence from the molecular dynamics simulation corroborates the present opinion. read less NOT USED (low confidence) S. Cheng and M. Chandross, “Atomic Origins of Friction Reduction in Metal Alloys,” Tribology Letters. 2012. link Times cited: 0 NOT USED (low confidence) L. P. Wang and T. V. Voorhis, “Communication: Hybrid ensembles for improved force matching.,” The Journal of chemical physics. 2010. link Times cited: 21 Abstract: Force matching is a method for parameterizing empirical pote… read moreAbstract: Force matching is a method for parameterizing empirical potentials in which the empirical parameters are fitted to a reference potential energy surface (PES). Typically, training data are sampled from a canonical ensemble generated with either the empirical potential or the reference PES. In this Communication, we show that sampling from either ensemble risks excluding critical regions of configuration space, leading to fitted potentials that deviate significantly from the reference PES. We present a hybrid ensemble which combines the Boltzmann probabilities of both potential surfaces into the fitting procedure, and we demonstrate that this technique improves the quality and stability of empirical potentials. read less NOT USED (low confidence) G. Grochola, S. Russo, and I. Snook, “A modified embedded atom method interatomic potential for alloy SiGe,” Chemical Physics Letters. 2010. link Times cited: 5 NOT USED (low confidence) G. Opletal, C. Feigl, G. Grochola, I. Snook, and S. Russo, “Elucidation of surface driven crystallization of icosahedral clusters,” Chemical Physics Letters. 2009. link Times cited: 6 NOT USED (low confidence) C. Feigl, G. Grochola, G. Opletal, I. Snook, and S. Russo, “A theoretical study of size and temperature dependent morphology transformations in gold nanoparticles,” Chemical Physics Letters. 2009. link Times cited: 5 NOT USED (low confidence) T. Järvi et al., “Development of a ReaxFF description for gold,” The European Physical Journal B. 2008. link Times cited: 61 NOT USED (low confidence) J. Li, X. Dai, S. Liang, K. Tai, Y. Kong, and B. Liu, “Interatomic potentials of the binary transition metal systems and some applications in materials physics,” Physics Reports. 2008. link Times cited: 110 NOT USED (low confidence) B. Trakhtenbrot, “Preface,” Fundam. Informaticae. 2004. link Times cited: 0 Abstract: Many practical control systems are subject to possible malfu… read moreAbstract: Many practical control systems are subject to possible malfunctions which may cause significant performance degradation and even instability of the system. To improve reliability, performance, and safety of dynamical systems, fault diagnosis techniques are receiving considerable attention both in research and applications and have been the subjects of intensive investigations. Fault detection, which acts as the first step of the fault diagnosis, is a binary decision process determining whether a fault has occurred or not. Fault isolation is to determine the location of the faulty component, while fault estimation is to online identify the size of the occurred fault. Compared with the problems of fault detection and isolation, fault estimation is more challenging. In this book, observer-fault estimation techniques are further investigated and new results related to fault estimation are presented. In Chap. 1, the background of fault estimation is given and motivations of our studies are presented in detail. In Chap. 2, the design of a multi-constrained full-order fault estimation observer (FFEO) with finite-frequency specifications is studied for continuous-time systems. By constructing an augmented system, a multi-constrained FFEO in finite-frequency domain is proposed to achieve fault estimation. Meanwhile, the presented FFEO can avoid the overdesign problem generated by the entire frequency domain by the generalized Kalman–Yakubovich–Popov (KYP) lemma. Furthermore, by introducing slack variables, improved results on FFEO design in different frequency domains are obtained such that different Lyapunov matrices can be separately designed for each constraint. In Chap. 3, a framework of fault estimation observer design in finite-frequency domain is proposed for discrete-time systems, including FFEO and reduced-order fault estimation observer (RFEO). A FFEO in finite-frequency domain is designed to achieve fault estimation by using the generalized KYP lemma to reduce conservatism generated by the entire frequency domain. Then, a RFEO is constructed, which results in a new fault estimator to realize fault estimation using current output information. Furthermore, improved results on FFEO and RFEO design with finite-frequency specifications are obtained. read less NOT USED (high confidence) J. Hörmann, C. Liu, Y. Meng, and L. Pastewka, “Molecular simulations of sliding on SDS surfactant films.,” The Journal of chemical physics. 2023. link Times cited: 0 Abstract: We use molecular dynamics simulations to study the frictiona… read moreAbstract: We use molecular dynamics simulations to study the frictional response of monolayers of the anionic surfactant sodium dodecyl sulfate and hemicylindrical aggregates physisorbed on gold. Our simulations of a sliding spherical asperity reveal the following two friction regimes: at low loads, the films show Amonton's friction with a friction force that rises linearly with normal load, and at high loads, the friction force is independent of the load as long as no direct solid-solid contact occurs. The transition between these two regimes happens when a single molecular layer is confined in the gap between the sliding bodies. The friction force at high loads on a monolayer rises monotonically with film density and drops slightly with the transition to hemicylindrical aggregates. This monotonous increase of friction force is compatible with a traditional plowing model of sliding friction. At low loads, the friction coefficient reaches a minimum at the intermediate surface concentrations. We attribute this behavior to a competition between adhesive forces, repulsion of the compressed film, and the onset of plowing. read less NOT USED (high confidence) P. Kang, Y. Wang, B. Wilson, J. Randrianalisoa, and Z. Qin, “Nanoparticle fragmentation at solid state under single picosecond laser pulse stimulation,” bioRxiv. 2021. link Times cited: 0 Abstract: Understanding the laser-nanomaterials interaction including … read moreAbstract: Understanding the laser-nanomaterials interaction including nanomaterial fragmentation has important implications in nanoparticle manufacturing, energy, and biomedical sciences. So far, three mechanisms of laser-induced fragmentation have been recognized including non-thermal processes and thermomechanical force under femtosecond pulses, and the phase transitions under nanosecond pulses. Here we show that single picosecond (ps) laser pulse stimulation leads to anomalous fragmentation of gold nanoparticles that deviates from these three mechanisms. The ps laser fragmentation was weakly dependent on particle size, and it resulted in a bimodal size distribution. Importantly, ps laser stimulation fragmented particles below the melting point and below the threshold for non-thermal mechanism. This study reveals a previously unknown regime of nanoparticle fragmentation. read less NOT USED (high confidence) L. B’etermin, M. Friedrich, and U. Stefanelli, “Lattice ground states for embedded-atom models in 2D and 3D,” Letters in Mathematical Physics. 2021. link Times cited: 5 NOT USED (high confidence) S. Y. Joshi and S. A. Deshmukh, “A review of advancements in coarse-grained molecular dynamics simulations,” Molecular Simulation. 2020. link Times cited: 89 Abstract: ABSTRACT Over the last few years, coarse-grained molecular d… read moreAbstract: ABSTRACT Over the last few years, coarse-grained molecular dynamics has emerged as a way to model large and complex systems in an efficient and inexpensive manner due to its lowered resolution, faster dynamics, and larger time steps. However, developing coarse-grained models and subsequently, the accurate interaction potentials (force-field parameters) is a challenging task. Traditional parameterisation techniques, although tedious, have been used extensively to develop CG models for a variety of solvent, soft-matter and biological systems. With the advent of sophisticated optimisation methods, machine learning, and hybrid approaches for force-field parameterisation, models with a higher degree of transferability and accuracy can be developed in a shorter period of time. We review here, some of these traditional and advanced parameterisation techniques while also shedding light on several transferable CG models developed in our group over the years using such an advanced method developed by us. These models, including solvents, polymers and biomolecules have helped us study important solute-solvent interactions and complex polymer architectures, thus paving a way to make experimentally verifiable observations. read less NOT USED (high confidence) S. Kumari and A. Dutta, “Nucleation of twinning dislocation loops in fcc metals,” arXiv: Materials Science. 2020. link Times cited: 5 NOT USED (high confidence) J. Chapman and R. Ramprasad, “Multiscale Modeling of Defect Phenomena in Platinum Using Machine Learning of Force Fields,” JOM. 2020. link Times cited: 5 NOT USED (high confidence) J. Chapman and R. Ramprasad, “Predicting the dynamic behavior of the mechanical properties of platinum with machine learning.,” The Journal of chemical physics. 2020. link Times cited: 2 Abstract: Over the last few decades, computational tools have been ins… read moreAbstract: Over the last few decades, computational tools have been instrumental in understanding the behavior of materials at the nano-meter length scale. Until recently, these tools have been dominated by two levels of theory: quantum mechanics (QM) based methods and semi-empirical/classical methods. The former are time-intensive but accurate and versatile, while the latter methods are fast but are significantly limited in veracity, versatility, and transferability. Recently, machine learning (ML) methods have shown the potential to bridge the gap between these two chasms due to their (i) low cost, (ii) accuracy, (iii) transferability, and (iv) ability to be iteratively improved. In this work, we further extend the scope of ML for atomistic simulations by capturing the temperature dependence of the mechanical and structural properties of bulk platinum through molecular dynamics simulations. We compare our results directly with experiments, showcasing that ML methods can be used to accurately capture large-scale materials phenomena that are out of reach of QM calculations. We also compare our predictions with those of a reliable embedded atom method potential. We conclude this work by discussing how ML methods can be used to push the boundaries of nano-scale materials research by bridging the gap between QM and experimental methods. read less NOT USED (high confidence) Q. Yang, W. A. Nanney, X. Hu, T. Ye, and A. Martini, “Nanoscale Friction of Hydrophilic and Hydrophobic Self-Assembled Monolayers in Water,” Tribology Letters. 2020. link Times cited: 3 NOT USED (high confidence) A. Lange, A. Samanta, T. Y. Olson, and S. Elhadj, “Quantized Grain Boundary States Promote Nanoparticle Alignment During Imperfect Oriented Attachment.,” Small. 2020. link Times cited: 8 Abstract: Oriented attachment (OA) has become a well-recognized mechan… read moreAbstract: Oriented attachment (OA) has become a well-recognized mechanism for the growth of metal, ceramic, and biomineral crystals. While many computational and experimental studies of OA have shown that particles can attach with some misorientation then rotate to remove adjoining grain boundaries, the underlying atomistic pathways for this "imperfect OA" process remain the subject of debate. In this study, molecular dynamics and in situ transmission electron microscopy (TEM) are used to probe the crystallographic evolution of up to 30 gold nanoparticles during aggregation. It is found that Imperfect OA occurs because 1) grain boundaries become quantized when their size is comparable to the separation between constituent dislocations and 2) kinetic barriers associated with the glide of grain boundary dislocations are small. In support of these findings, TEM experiments show the formation of a single crystal aggregate after annealing nine initially misoriented, agglomerated particles with evidence of dislocation activity and twin formation during particle/grain alignment. These observations motivate future work on assembled nanocrystals with tailored defects and call for a revision of Read-Shockley models for grain boundary energies in nanocrystalline materials. read less NOT USED (high confidence) V. Gorshkov, V. Tereshchuk, and P. Sareh, “Diversity of anisotropy effects in the breakup of metallic FCC nanowires into ordered nanodroplet chains,” CrystEngComm. 2020. link Times cited: 7 Abstract: We have analysed the expressed manifestation of the anisotro… read moreAbstract: We have analysed the expressed manifestation of the anisotropy of surface energy density in the dynamics of ultrathin nanowires, which break up into disjointed clusters when annealed below their melting temperature. The breakup process is studied for different temperatures and orientations of the nanowire axis relative to its internal crystal structure using the Monte Carlo kinetic method. We have also presented an approximate analytical model of the instability of nanowires. Generally, the interpretation of experimental results refers to the theoretical model developed by Nichols and Mullins, which is based on conceptions about the Rayleigh instability of liquid jets. In both cases, the theories – which do not take into account the anisotropy of surface energy density – predict the breakup of a nanowire/liquid jet with radius r into fragments with an average length Λ = 9r. However, the observed value, Λ/r, often deviates from 9 either to lower values or to substantially greater ones (up to 24–30). Our results explain various observed features of the breakup and the significant variations in the values of its parameter Λ/r depending on experimental conditions. In particular, the ambiguous role of exchange by atoms of the surface of a nanowire with a surrounding layer of free atoms formed as a result of their rather intensive sublimation, which occurs in a number of cases, has been investigated. We have shown that this exchange can lead both to a decrease and to a significant increase in the parameter Λ/r. The obtained results could be potentially useful in applications such as the development of optical waveguides based on ordered nanoparticle chains. read less NOT USED (high confidence) R. Essajai, “Study of Structural and Melting Properties of Gold Nanorods,” Nanorods and Nanocomposites. 2019. link Times cited: 0 Abstract: MD simulations combined with the embedded-atom method have b… read moreAbstract: MD simulations combined with the embedded-atom method have been applied to study the structural and melting properties of gold nanorods (AuNRs) of different sizes. The simulation results for the actual structure of AuNRs obtained after energy minimization processes revealed that the AuNRs with largest cohesive energies tend to be structurally more stable than those with smallest ones. Then, it was found that each actual structure of AuNR is classified as an irregular structure composed of a crystalline gold core covered by an amorphous gold shell. In addi-tion, the results showed that the melting of the AuNR surface is an inhomogeneous, gradually occurring process. Besides, it was established that the premelting ratio is inversely correlated with the AuNR size, indicating that the premelting phenomenon is more pronounced in large NP sizes than in small ones. read less NOT USED (high confidence) A. Gola, R. Schwaiger, P. Gumbsch, and L. Pastewka, “Pattern formation during deformation of metallic nanolaminates,” Physical Review Materials. 2019. link Times cited: 14 Abstract: We used nonequilibrium molecular dynamics simulations to stu… read moreAbstract: We used nonequilibrium molecular dynamics simulations to study the shear deformation of metallic composites composed of alternating layers of Cu and Au. Our simulations reveal the formation of "vortices" or "swirls" if the bimaterial interfaces are atomically rough and if none of the {111} planes that accommodate slip in fcc materials is exactly parallel to this interface. We trace the formation of these patterns back to grain rotation, induced by hindering dislocations from crossing the bimaterial interface. The instability is accompanied by shear-softening of the material. These calculations shed new light on recent observations of pattern formation in plastic flow, mechanical mixing of materials and the common formation of a tribomutation layer in tribologically loaded systems. read less NOT USED (high confidence) A. Gola and L. Pastewka, “Scratching Cu|Au Nanolaminates,” Lubricants. 2019. link Times cited: 3 Abstract: We used molecular dynamics simulations to study the scratchi… read moreAbstract: We used molecular dynamics simulations to study the scratching of Cu|Au nanolaminates of 5 nm layer thickness with a nanoscale indenter of 15 nm radius at normal forces between 0.5 μ N and 2 μ N. Our simulations show that Au layers wear quickly while Cu layers are more resistant to wear. Plowing was accompanied by the roughening of the Cu|Au heterointerface that lead to the folding of the nanolaminate structure at the edge of the wear track. Our explorative simulations hint at the complex deformation processes occurring in nanolaminates under tribological load. read less NOT USED (high confidence) S. Verkhoturov et al., “Hypervelocity cluster ion impacts on free standing graphene: Experiment, theory, and applications.,” The Journal of chemical physics. 2019. link Times cited: 9 Abstract: We present results from experiments and molecular dynamics (… read moreAbstract: We present results from experiments and molecular dynamics (MD) simulations obtained with C60 and Au400 impacting on free-standing graphene, graphene oxide (GO), and graphene-supported molecular layers. The experiments were run on custom-built ToF reflectron mass spectrometers with C60 and Au-LMIS sources with acceleration potentials generating 50 keV C60 2+ and 440-540 keV Au400 4+. Bombardment-detection was in the same mode as MD simulation, i.e., a sequence of individual projectile impacts with separate collection/identification of the ejecta from each impact in either the forward (transmission) or backward (reflection) direction. For C60 impacts on single layer graphene, the secondary ion (SI) yields for C2 and C4 emitted in transmission are ∼0.1 (10%). Similar yields were observed for analyte-specific ions from submonolayer deposits of phenylalanine. MD simulations show that graphene acts as a trampoline, i.e., they can be ejected without destruction. Another topic investigated dealt with the chemical composition of free-standing GO. The elemental composition was found to be approximately COH2. We have also studied the impact of Au400 clusters on graphene. Again SI yields were high (e.g., 1.25 C-/impact). 90-100 Au atoms evaporate off the exiting projectile which experiences an energy loss of ∼72 keV. The latter is a summation of energy spent on rupturing the graphene, ejecting carbon atoms and clusters and a dipole projectile/hole interaction. The charge distribution of the exiting projectiles is ∼50% neutrals and ∼25% either negatively or positively charged. We infer that free-standing graphene enables detection of attomole to zeptomole deposits of analyte via cluster-SI mass spectrometry. read less NOT USED (high confidence) Z. Wang, “Lubricity of graphene on rough Au surfaces,” Journal of Physics D: Applied Physics. 2018. link Times cited: 10 Abstract: This paper studies the lubricating properties of graphene on… read moreAbstract: This paper studies the lubricating properties of graphene on randomly rough Au surfaces in sliding nanofriction using molecular dynamics. It is shown that the friction and the consequent heat dissipation decrease more than an order of magnitude in the presence of graphene. The performance of graphene nanoribbons as lubricants is, however, limited because of detachment and displacement at the interface. Sliding contacts lubricated with a stretched graphene sheet exhibit low friction, but possibly also low structural stability. This suggests that the graphene-substrate adherence could be crucial for the lubricity of two-dimensional materials on rough metal surfaces. read less NOT USED (high confidence) Z. Chen et al., “Interatomic Potential in the Nonequilibrium Warm Dense Matter Regime.,” Physical review letters. 2018. link Times cited: 18 Abstract: We present a new measurement of lattice disassembly times in… read moreAbstract: We present a new measurement of lattice disassembly times in femtosecond-laser-heated polycrystalline Au nanofoils. The results are compared with molecular dynamics simulations incorporating a highly optimized, embedded-atom-method interatomic potential. For absorbed energy densities of 0.9-4.3 MJ/kg, the agreement between the experiment and simulation reveals a single-crystal-like behavior of homogeneous melting and corroborates the applicability of the interatomic potential in the nonequilibrium warm dense matter regime. For energy densities below 0.9 MJ/kg, the measurement is consistent with nanocrystal behavior where melting is initiated at the grain boundaries. read less NOT USED (high confidence) V. Samsonov, A. G. Bembel,’ A. Kartoshkin, S. Vasilyev, and I. Talyzin, “Molecular dynamics and thermodynamic simulations of segregation phenomena in binary metal nanoparticles,” Journal of Thermal Analysis and Calorimetry. 2018. link Times cited: 22 NOT USED (high confidence) Y. Hwang, C. Pan, Y.-X. Lu, S. Jian, and J. Juang, “Deformation behaviors of Au nanotubes under torsion by molecular dynamics simulations,” AIP Advances. 2018. link Times cited: 3 Abstract: In this study, the mechanical deformation behaviors of Au na… read moreAbstract: In this study, the mechanical deformation behaviors of Au nanotubes (Au-NTs) under torsional stress are investigated using molecular dynamics (MD) simulations. The inter-atomic interaction is modeled using the embedded-atom potential. In particular, the effects of loading rate, thickness and length of the nanotube, as well as the thermal effects were systematically explored. The results indicated that higher loading rate, longer length and thinner wall thickness all led to a larger value of critical torsional angle (θcr), which signifies the onset of plastic deformation. On the other hand, θcr decreases with increasing temperature in all simulated results. Moreover, the torsional buckling deformation behavior and geometrical instability are found to strongly depend on the length of Au-NTs, the applied strain rate and temperature with vastly different underlying mechanisms. read less NOT USED (high confidence) X. Hu, W. A. Nanney, K. Umeda, T. Ye, and A. Martini, “Combined Experimental and Simulation Study of Amplitude Modulation Atomic Force Microscopy Measurements of Self-Assembled Monolayers in Water.,” Langmuir : the ACS journal of surfaces and colloids. 2018. link Times cited: 13 Abstract: Atomic force microscopy (AFM) can be used to measure surface… read moreAbstract: Atomic force microscopy (AFM) can be used to measure surface properties at the nanoscale. However, interpretation of measurements from amplitude modulation AFM (AM-AFM) in liquid is not straightforward due to the interactions between the AFM tip, the surface being imaged, and the water. In this work, amplitude-distance measurements and molecular dynamics simulations of AM-AFM were employed to study the effect of surface chemistry on the amplitude of tip oscillation in water. The sample surfaces consisted of self-assembled monolayers where the hydrophilicity or hydrophobicity was determined by the terminal group of the alkanethiols. Analysis showed that surface chemical composition influences the hydration structure near the interface which affects the forces experienced by the tip and in turn changes the amplitude profile. This observation could aid our understanding of AM-AFM measurements of interfacial phenomena on various surfaces in water. read less NOT USED (high confidence) A. Gola and L. Pastewka, “Embedded atom method potential for studying mechanical properties of binary Cu–Au alloys,” Modelling and Simulation in Materials Science and Engineering. 2018. link Times cited: 13 Abstract: We present an embedded atom method (EAM) potential for the b… read moreAbstract: We present an embedded atom method (EAM) potential for the binary Cu–Au system. The unary phases are described by two well-tested unary EAM potentials for Cu and Au. We fitted the interaction between Cu and Au to experimental properties of the binary intermetallic phases Cu3Au, CuAu and CuAu3. Particular attention has been paid to reproducing stacking fault energies in order to obtain a potential suitable for studying deformation in this binary system. The resulting energies, lattice constant, elastic properties and melting points are in good agreement with available experimental data. We use nested sampling to show that our potential reproduces the phase boundaries between intermetallic phases and the disordered face-centered cubic solid solution. We benchmark our potential against four popular Cu–Au EAM parameterizations and density-functional theory calculations. read less NOT USED (high confidence) L. Hale, Z. Trautt, and C. Becker, “Evaluating variability with atomistic simulations: the effect of potential and calculation methodology on the modeling of lattice and elastic constants,” Modelling and Simulation in Materials Science and Engineering. 2018. link Times cited: 40 Abstract: Atomistic simulations using classical interatomic potentials… read moreAbstract: Atomistic simulations using classical interatomic potentials are powerful investigative tools linking atomic structures to dynamic properties and behaviors. It is well known that different interatomic potentials produce different results, thus making it necessary to characterize potentials based on how they predict basic properties. Doing so makes it possible to compare existing interatomic models in order to select those best suited for specific use cases, and to identify any limitations of the models that may lead to unrealistic responses. While the methods for obtaining many of these properties are often thought of as simple calculations, there are many underlying aspects that can lead to variability in the reported property values. For instance, multiple methods may exist for computing the same property and values may be sensitive to certain simulation parameters. Here, we introduce a new high-throughput computational framework that encodes various simulation methodologies as Python calculation scripts. Three distinct methods for evaluating the lattice and elastic constants of bulk crystal structures are implemented and used to evaluate the properties across 120 interatomic potentials, 18 crystal prototypes, and all possible combinations of unique lattice site and elemental model pairings. Analysis of the results reveals which potentials and crystal prototypes are sensitive to the calculation methods and parameters, and it assists with the verification of potentials, methods, and molecular dynamics software. The results, calculation scripts, and computational infrastructure are self-contained and openly available to support researchers in performing meaningful simulations. read less NOT USED (high confidence) S. Xu, S. Chavoshi, and Y. Su, “Deformation Mechanisms in Nanotwinned Tungsten Nanopillars: Effects of Coherent Twin Boundary Spacing,” physica status solidi (RRL) – Rapid Research Letters. 2018. link Times cited: 20 Abstract: Nano‐scale coherent twin boundaries (CTBs) significantly alt… read moreAbstract: Nano‐scale coherent twin boundaries (CTBs) significantly alter the mechanical and electrical properties of metallic materials. Despite a number of studies of the nanotwinned nanopillars in face‐centered cubic metals, investigations of them in body‐centered cubic (BCC) systems are rare. In this Letter, we explore the uniaxial deformation mechanisms of BCC tungsten nanopillars containing nano‐scale {112} CTBs using molecular dynamics (MD) simulations. Our work reveals a novel tension–compression asymmetric stress–strain response and deformation behavior, in conjunction with the effects of CTB spacing. With a relatively large CTB spacing, the plastic deformation in nanotwinned nanopillars is mainly controlled by dislocation nucleation from surface/CTB intersections, gliding on distant and adjacent slip planes under tensile and compressive loading, respectively; as a result, the tensile yield stress is almost invariant with respect to the CTB spacing, while the compressive yield stress increases with a decreasing CTB spacing. As the CTB spacing reduces to 1 nm, detwinning, exhibited by annihilation of {112} twin layers as a result of partial dislocations gliding on CTBs, is observed in both tension and compression; at higher strains, however, {111} incoherent twin boundaries, whose resistance to cracking contributes to strain hardening, are formed under tensile loading but not under compressive loading. read less NOT USED (high confidence) S. Xu, J. Startt, T. Payne, C. Deo, and D. McDowell, “Size-dependent plastic deformation of twinned nanopillars in body-centered cubic tungsten,” Journal of Applied Physics. 2017. link Times cited: 31 Abstract: Compared with face-centered cubic metals, twinned nanopillar… read moreAbstract: Compared with face-centered cubic metals, twinned nanopillars in body-centered cubic (BCC) systems are much less explored partly due to the more complicated plastic deformation behavior and a lack of reliable interatomic potentials for the latter. In this paper, the fault energies predicted by two semi-empirical interatomic potentials in BCC tungsten (W) are first benchmarked against density functional theory calculations. Then, the more accurate potential is employed in large scale molecular dynamics simulations of tensile and compressive loading of twinned nanopillars in BCC W with different cross sectional shapes and sizes. A single crystal, a twinned crystal, and single crystalline nanopillars are also studied as references. Analyses of the stress-strain response and defect nucleation reveal a strong tension-compression asymmetry and a weak pillar size dependence in the yield strength. Under both tensile and compressive loading, plastic deformation in the twinned nanopillars is dominated by dislocatio... read less NOT USED (high confidence) A. Wei and C. Deng, “Adsorption of Protein on a Au Surface Studied by All-Atom Atomistic Simulations,” Journal of Physical Chemistry C. 2016. link Times cited: 3 Abstract: In this work, the adsorption of protein on a Au surface coat… read moreAbstract: In this work, the adsorption of protein on a Au surface coated by self-assembled monolayers (SAMs) of alkanethiol chains is studied by molecular dynamics simulations with an all-atom model. Particularly, a more realistic embedded-atom method potential has been used to characterize the Au–Au interactions in the system as compared to previous studies. With this all-atom model, many experimental observations have been reproduced from the simulations. It is found that the SAMs have the lowest adsorption energy on the Au(111) surface where the alkanethiol chains form a well-ordered (√3×√3)R30° triangular lattice at 300 K. Furthermore, it is confirmed that carboxyl-terminated SAMs are more effective to absorb proteins than the methyl-terminated SAMs. On the basis of the simulation results, we propose that the experimentally observed aggregation of protein–Au nanoparticle conjugates is mainly due to the electrostatic interactions between protein amino acids and carboxyl-terminated SAMs from multiple Au surfaces. read less NOT USED (high confidence) G. Grochola, I. Snook, and S. Russo, “Phase separated reconstruction patterns on strained FCC (111) metal surfaces,” Molecular Simulation. 2016. link Times cited: 3 Abstract: In this paper, we use the newly developed shear-induced reco… read moreAbstract: In this paper, we use the newly developed shear-induced reconstruction computer simulation method to explore various phase separated reconstruction patterns on strained Au(111), Pt(111), Ni(111) and alloy Ag/Pt(111) systems via molecular dynamic computer simulations. We find that specific surface reconstruction patterns are not confined to specific metallic systems; instead the results show that almost any reconstruction pattern could arise in almost any of the model systems dependent on the substrate to reconstruction layer lattice constant mismatch, and the substrate to reconstruction layer interaction strength. read less NOT USED (high confidence) H.-L. Chen, C. Su, S. Ju, S.-H. Liu, and H. T. Chen, “Local structural evolution of Fe54C18Cr16Mo12 bulk metallic glass during tensile deformation and a temperature elevation process: a molecular dynamics study,” RSC Advances. 2015. link Times cited: 3 Abstract: The mechanical and thermal properties of Fe54C18Cr16Mo12 bul… read moreAbstract: The mechanical and thermal properties of Fe54C18Cr16Mo12 bulk metallic glasses (BMGs) were investigated by a molecular dynamics simulation with the 2NN modified embedded-atom method (MEAM) potential. The fitting process of the cross-element parameters of 2NN MEAM (Fe–C, Fe–Cr, Fe–Mo, C–Cr, C–Mo, and Cr–Mo) was carried out first by the force matching method (FMM) on the basis of the reference data from density functional theory (DFT) calculations. With these fitted parameters, the structure of Fe54C18Cr16Mo12 BMG was constructed by the simulated-annealing basin-hopping (SABH) method, and the angle distribution range of the X-ray diffraction profile of the predicted Fe54C18Cr16Mo12 BMG closely matches that of the experiment profile, indicating the fitted 2NN MEAM parameters can accurately reflect the interatomic interactions of Fe54C18Cr16Mo12 BMG. The Honeycutt–Andersen (HA) index analysis results show a significant percentage of icosahedral-like structures within Fe54C18Cr16Mo12 BMG, which suggests an amorphous state. According to the tensile test results, the estimated Young's modulus of Fe54Cr16Mo12C18 bulk metallic glass is about 139 GPa and the large plastic region of the stress–strain curve shows that the Fe54C18Cr16Mo12 BMG possesses good ductility. Local strain distribution was used to analyze the deformation mechanism, and the results show that a shear band develops homogeneously with the tensile fracture angle (θT) at about 50 degrees, in agreement with experimental results 45° < θT < 90°. For the temperature elevation results, the discontinuity of the enthalpy–temperature profile indicates the melting point of Fe54Cr16Mo12C18 BMG is about 1310 K. The diffusion coefficients near the melting point were derived by the Einstein equation from the mean-square-displacement (MSD) profiles between 800–1400 K. On the basis of diffusion coefficients at different temperatures, the diffusion barriers of Fe54Cr16Mo12C18 can be determined by the Arrhenius equation. The diffusion barriers of total for Fe, Cr, Mo, C are 31.88, 24.68, 35.26, 22.50 and 31.79 kJ mol−1, respectively. The diffusion barriers of Fe and Cr atoms are relatively lower, indicating Fe and Cr atoms more easily diffuse with the increasing temperature. read less NOT USED (high confidence) H.-L. Chen, S. Ju, T.-Y. Wu, S.-H. Liu, and H.-T. Chen, “Investigation of the mechanical properties and local structural evolution of Ti60Zr10Ta15Si15 bulk metallic glass during tensile deformation: a molecular dynamics study,” RSC Advances. 2015. link Times cited: 15 Abstract: Ti60Zr10Ta15Si15 bulk metallic glass (BMG) has been proven t… read moreAbstract: Ti60Zr10Ta15Si15 bulk metallic glass (BMG) has been proven to have potential for use in orthopedic bone fixation devices, and further studies on its structural properties and deformation mechanism under uniaxial tension have been conducted using molecular dynamics (MD) simulations. The Honeycutt–Andersen (HA) index analysis, Voronoi tessellation method and Warren–Cowley short-range order parameter are employed to investigate its structural properties. The results show a high content of icosahedral-like structures, which suggests an amorphous state and a trend for silicon to pair with a metal atom. In its tensile test, the Ti60Zr10Ta15Si15 bulk metallic glass showed good ductility and an estimated Young's modulus of about 93 GPa, which is close to the experimental value. Local strain distribution was used to analyze the deformation mechanism, and the results show that shear bands develop homogeneously, which enhances the plasticity. The Voronoi tessellation analysis and HA index were used to further investigate the plastic/elastic deformation mechanism. The results of the HA analysis show that icosahedral local structures (1551, 1541, 1431) transfer to less dense structures (1422 and 1311), which shows an increase of open volume which can be attributed to the formation of the shear bands. In addition, the Voronoi tessellation analysis also shows a notable change from perfect icosahedra to distorted icosahedra. Further investigation shows the variations of the Voronoi index are mostly the Ti and Si-centered clusters. This suggests that the structures around Ti and Si atoms undergo a severe evolution during the tension process. read less NOT USED (high confidence) R. Grenier, Q. To, M. P. de Lara-Castells, and C. Léonard, “Argon Interaction with Gold Surfaces: Ab Initio-Assisted Determination of Pair Ar-Au Potentials for Molecular Dynamics Simulations.,” The journal of physical chemistry. A. 2015. link Times cited: 17 Abstract: Global potentials for the interaction between the Ar atom an… read moreAbstract: Global potentials for the interaction between the Ar atom and gold surfaces are investigated and Ar-Au pair potentials suitable for molecular dynamics simulations are derived. Using a periodic plane-wave representation of the electronic wave function, the nonlocal van-der-Waals vdW-DF2 and vdW-OptB86 approaches have been proved to describe better the interaction. These global interaction potentials have been decomposed to produce pair potentials. Then, the pair potentials have been compared with those derived by combining the dispersionless density functional dlDF for the repulsive part with an effective pairwise dispersion interaction. These repulsive potentials have been obtained from the decomposition of the repulsive interaction between the Ar atom and the Au2 and Au4 clusters and the dispersion coefficients have been evaluated by means of ab initio calculations on the Ar+Au2 complex using symmetry adapted perturbation theory. The pair potentials agree very well with those evaluated through periodic vdW-DF2 calculations. For benchmarking purposes, CCSD(T) calculations have also been performed for the ArAu and Ar+Au2 systems using large basis sets and extrapolations to the complete basis set limit. This work highlights that ab initio calculations using very small surface clusters can be used either as an independent cross-check to compare the performance of state-of-the-art vdW-corrected periodic DFT approaches or, directly, to calculate the pair potentials necessary in further molecular dynamics calculations. read less NOT USED (high confidence) S.-H. Liu, W. Saidi, Y. Zhou, and K. Fichthorn, “Synthesis of 111-Faceted Au Nanocrystals Mediated by Polyvinylpyrrolidone: Insights from Density-Functional Theory and Molecular Dynamics,” Journal of Physical Chemistry C. 2015. link Times cited: 24 Abstract: We use density-functional theory (DFT) and molecular dynamic… read moreAbstract: We use density-functional theory (DFT) and molecular dynamics (MD) to resolve the role of polyvinylpyrrolidone (PVP) in the shape-selective synthesis of Au nanostructures. Using DFT, we probe the adsorption-induced surface energies and spatially resolved binding of PVP monomer analogs on Au(111), Au(100), and (5 × 1) Au(100)-hex. These calculations suggest that {111} facets should be prevalent in Au nanostructures grown with the help of PVP. We explore the role of solvent and find that, while solvent weakens binding, it does not change the trends we observe in vacuum. We fit an ad hoc interatomic potential to the DFT results so we can describe the binding of PVP to the Au surfaces. Using MD simulations based on this potential, we investigate the PVP-induced surface energies, PVP binding affinities, and oxygen density profile of atactic PVP icosamers on Au(111) and (5 × 1) Au(100)-hex. We conclude that {111}-faceted Au nanocrystals are preferred in PVP-mediated synthesis of Au nanostructures. The reconstru... read less NOT USED (high confidence) H.-L. Chen, S. Ju, T.-Y. Wu, J. Hsieh, and S.-H. Liu, “Investigation of Zr and Si diffusion behaviors during reactive diffusion – a molecular dynamics study,” RSC Advances. 2015. link Times cited: 8 Abstract: Molecular dynamics simulation was used to investigate the di… read moreAbstract: Molecular dynamics simulation was used to investigate the diffusion behaviors of Zr and Si atoms during a reactive diffusion which produces Zr silicide. The simulation results were compared with those in Roy's experimental results. The profiles of mean square displacements (MSDs) of Zr and Si atoms at different temperatures were first used to evaluate the melting point above which the significant inter-diffusions of Zr and Si atom occur. The diffusion coefficients near the melting point were derived by the Einstein equation from MSD profiles. On the basis of diffusion coefficients at different temperatures, the diffusion barriers of Zr and Si atoms can be calculated by the Arrhenius equation. Compared to the corresponding experimental values, the predicted diffusion barriers at the Zr–Si interface were 23 times lower than the measured values in Roy's study. The main reason for this is that the Zr and Si atoms within the inter-diffusion region form different local ZrSi crystal alloys in the experiment, resulting in the lower diffusion coefficients and higher diffusion barriers found in the experimental observation. read less NOT USED (high confidence) C. Becker et al., “Thermodynamic modelling of liquids: CALPHAD approaches and contributions from statistical physics,” physica status solidi (b). 2014. link Times cited: 32 Abstract: We describe current approaches to thermodynamic modelling of… read moreAbstract: We describe current approaches to thermodynamic modelling of liquids for the CALPHAD method, the use of available experimental methods and results in this type of modelling, and considerations in the use of atomic‐scale simulation methods to inform a CALPHAD approach. We begin with an overview of the formalism currently used in CALPHAD to describe the temperature dependence of the liquid Gibbs free energy and outline opportunities for improvement by reviewing the current physical understanding of the liquid. Brief descriptions of experimental methods for extracting high‐temperature data on liquids and the preparation of undercooled liquid samples are presented. Properties of a well‐determined substance, B2 O3, including the glass transition, are then discussed in detail to emphasize specific modelling requirements for the liquid. We then examine the two‐state model proposed for CALPHAD in detail and compare results with experiment and theory, where available. We further examine the contributions of atomic‐scale methods to the understanding of liquids and their potential for supplementing available data. We discuss molecular dynamics (MD) and Monte Carlo methods that employ atomic interactions from classical interatomic potentials, as well as contributions from ab initio MD. We conclude with a summary of our findings. read less NOT USED (high confidence) W. Ong, S. Rupich, D. Talapin, A. McGaughey, and J. Malen, “Surface chemistry mediates thermal transport in three-dimensional nanocrystal arrays.,” Nature materials. 2013. link Times cited: 198 NOT USED (high confidence) Y. Gan and S. Jiang, “Ultrafast laser-induced premelting and structural transformation of gold nanorod,” Journal of Applied Physics. 2013. link Times cited: 32 Abstract: Femtosecond laser irradiation of a gold nanorod has been sim… read moreAbstract: Femtosecond laser irradiation of a gold nanorod has been simulated by a method that couples two-temperature model into molecular dynamics. Numerical results show that the surface premelting occurs prior to the initiation of planar defect and propagates from the surface layer into the inside of nanorod. Pressure relaxation leads to high-frequency temperature oscillation and two-way transformation between fcc and disordered atoms produced by the dynamic stresses. Partial dislocation cores are initiated on the crystal surfaces due to high stresses, and then noticeable planar defects including stacking faults and twin boundaries on {111} close-packed planes are developed. Finally, only parallel twin boundaries are present in the nanorod, showing favorable agreement with the experimental observation. read less NOT USED (high confidence) M. Backman, N. Juslin, and K. Nordlund, “Bond order potential for gold,” The European Physical Journal B. 2012. link Times cited: 11 NOT USED (high confidence) Y. Lu, J. Song, J. Huang, and J. Lou, “Surface dislocation nucleation mediated deformation and ultrahigh strength in sub-10-nm gold nanowires,” Nano Research. 2011. link Times cited: 81 NOT USED (high confidence) H. Sheng, M. Kramer, A. Cadien, T. Fujita, and M. Chen, “Highly optimized embedded-atom-method potentials for fourteen fcc metals,” Physical Review B. 2011. link Times cited: 387 Abstract: Highly optimized embedded-atom-method (EAM) potentials have … read moreAbstract: Highly optimized embedded-atom-method (EAM) potentials have been developed for 14 face-centered-cubic (fcc) elements across the periodic table. The potentials were developed by fitting the potential-energy surface (PES) of each element derived from high-precision first-principles calculations. The as-derived potential-energy surfaces were shifted and scaled to match experimental reference data. In constructing the PES, a variety of properties of the elements were considered, including lattice dynamics, mechanical properties, thermal behavior, energetics of competing crystal structures, defects, deformation paths, liquid structures, and so forth. For each element, the constructed EAM potentials were tested against the experiment data pertaining to thermal expansion, melting, and liquid dynamics via molecular dynamics computer simulation. The as-developed potentials demonstrate high fidelity and robustness. Owing to their improved accuracy and wide applicability, the potentials are suitable for high-quality atomistic computer simulation of practical applications. read less NOT USED (high confidence) M. Chassagne, M. Legros, and D. Rodney, “Atomic-scale simulation of screw dislocation/coherent twin boundary interaction in Al, Au, Cu and Ni,” Acta Materialia. 2011. link Times cited: 124 NOT USED (high confidence) Y. Chui, G. Opletal, I. Snook, and S. Russo, “Modeling the crystallization of gold nanoclusters—the effect of the potential energy function,” Journal of Physics: Condensed Matter. 2009. link Times cited: 6 Abstract: The crystallization dynamics of 5083 atom gold nanoclusters,… read moreAbstract: The crystallization dynamics of 5083 atom gold nanoclusters, which were quenched from the melt, were studied by molecular dynamics (MD) using the EAM ‘Glue’ and ‘Force-matched’ potentials to compare and contrast how the crystallization dynamics is affected by these potential energy functions. MD simulations from each potential showed the formation of gold nanoclusters of icosahedral morphology during the quenching process, which is in good agreement with the experimental studies of gold nanoclusters formed under vacuum. The effect of the potential on the evolution of cluster (surface and interior) morphology during the crystallization process is discussed. read less NOT USED (high confidence) G. Grochola, I. Snook, and S. Russo, “Influence of substrate morphology on the growth of gold nanoparticles.,” The Journal of chemical physics. 2008. link Times cited: 6 Abstract: We have simulated the vacuum deposition and subsequent growt… read moreAbstract: We have simulated the vacuum deposition and subsequent growth of gold nanoparticles on various substrates in order to explore the effects that substrate morphology has on the resultant morphology of gold nanoparticles. The substrates and conditions explored included, the three low index faces, namely, (111), (100), and (110) for both fcc and bcc crystalline substrate structures, including various substrate lattice constants and temperatures. Firstly, we cataloged the major nanoparticle morphologies produced overall. While some substrates were found to produce a mixture of the main nanoparticle morphologies we were successful in identifying certain substrates and temperature conditions for which only I(h), D(h), or certain fcc crystalline nanoparticles can be grown almost exclusively. The substrate characteristics, temperature conditions, and governing growth dynamics are analyzed. We shed light on the balance between substrate influences and vacuum growth tendencies. From observations we can speculate that a substrate alters both the free energy stability of gold nanoparticles and/or the free energy barriers to transformation between certain morphologies. As such we find that substrates are an effective tool in templating the selective growth of desired nanoparticles or surface nanostructures. read less NOT USED (high confidence) G. Grochola, S. Russo, and I. Snook, “On the formation mechanism of the ‘pancake’ decahedron gold nanoparticle.,” The Journal of chemical physics. 2007. link Times cited: 10 Abstract: We have studied the thermodynamic and kinetic growth mechani… read moreAbstract: We have studied the thermodynamic and kinetic growth mechanisms behind the formation of the "pancake" decahedron (D(h)) gold nanoparticle using computer simulation. Free energy calculations showed that the full pancake morphology is thermodynamically unstable across all the nanoparticle size ranges studied. However, from observations of growth simulations we discovered that a kinetic transport mechanism plays a significant contributing role in the formation process through a transfer of adatoms from the top and bottom (111) D(h) faces to the side (100) faces. More specifically we observed how diffusing adatoms on the (111) face are at times "pulled" off this face and into the (111)-(100) edge of the D(h), forcing a row of (100) side atoms into a (1x5) hexagonal reconstruction. Subsequently, this row of atoms was observed to buckle and then deconstruct forcing adatoms out onto the (100) side face completing the transfer. This transport mechanism is shown to be the main kinetic driving force behind the growth of the thermodynamically unstable pancake D(h) nanoparticle. The observed mechanism has implications for the nonequilibrium morphologies of nanoparticles involving a (100)-(111) surface boundary, especially for systems with surface reconstructions which increase the density of the surface. read less NOT USED (high confidence) G. Grochola, I. Snook, and S. Russo, “On the relative stabilities of gold nanoparticles.,” The Journal of chemical physics. 2007. link Times cited: 19 Abstract: We calculate and compare the relative free energies of ideal… read moreAbstract: We calculate and compare the relative free energies of ideal/pristine gold nanoparticles for morphologies produced previously in vapor synthesis computer simulations. The results in conjunction with previous work provide a unique and direct quantitative comparison between ideal thermodynamics and kinetics in the synthesis of gold nanoparticles for an identical system. The ideal/pristine free energies suggest that the I(h) morphology was the most stable structure up to the 147(I(h)) followed by the TO(h) for all the remaining nanoparticle sizes. A grouping of m-D(h) structures was identified in the size range N=146-318 with stabilities which were very close to the most stable I(h) and TO(h) structures. The free energy analysis was somewhat at odds with population statistics obtained from our kinetic growth simulations where the I(h) dominated and where very little presumably stable TO(h) nanoparticles were produced, implying that kinetic mechanisms are more influential than thermodynamic considerations. On the other hand other possible reasons for such discrepancies are discussed; one of these includes an interesting observation where the I(h) morphology was found to have a unique ability to incorporate exposed surface disorder such as adatoms into stable hexagonal surface structures through internal and surface structural rearrangements, leading to a possible enhancement in stabilities of I(h)-type morphologies. read less NOT USED (high confidence) G. Grochola, I. Snook, and S. Russo, “Computational modeling of nanorod growth.,” The Journal of chemical physics. 2007. link Times cited: 53 Abstract: In this computational study, we used molecular dynamics and … read moreAbstract: In this computational study, we used molecular dynamics and the embedded atom method to successfully reproduce the growth of gold nanorod morphologies from starting spherical seeds in the presence of model surfactants. The surfactant model was developed through extensive systematic attempts aimed at inducing nonisotropic nanoparticle growth in strictly isotropic computational growth environments. The aim of this study was to identify key properties of the surfactants which were most important for the successful anisotropic growth of nanorods. The observed surface and collective dynamics of surfactants shed light on the likely growth phenomena of real nanoprods. These phenomena include the initial thermodynamically driven selective adsorption, segregation, and orientation of the surfactant groups on specific crystallographic surfaces of spherical nanoparticle seeds and the kinetic elongation of unstable surfaces due to growth inhibiting surfactants on those surfaces. Interestingly, the model not only reproduced the growth of nearly all known nanorod morphologies when starting from an initial fcc or fivefold seed but also reproduced the experimentally observed failure of nanorod growth when starting from spherical nanoparticles such as the I(h) morphology or morphologies containing a single twinning plane. Nanorod morphologies observed in this work included fivefold nanorods, fcc crystalline nanorods in the [100] direction and [112] directions and the more exotic "dumbell-like" nanorods. Non-nanorod morphologies observed included the I(h) and the nanoprism morphology. Some of the key properties of the most successful surfactants seemed to be suggestive of the important but little understood role played by silver ions in the growth process of real nanorods. read less NOT USED (high confidence) G. Grochola, S. Russo, and I. Snook, “On morphologies of gold nanoparticles grown from molecular dynamics simulation.,” The Journal of chemical physics. 2007. link Times cited: 29 Abstract: The authors use a newly fitted gold embedded atom method pot… read moreAbstract: The authors use a newly fitted gold embedded atom method potential to simulate the initial nucleation, coalescence, and kinetic growth process of vapor synthesized gold nanoparticles. Overall the population statistics obtained in this work seemed to mirror closely recent experimental HREM observations by Koga and Sugawara [Surf. Sci. 529, 23 (2003)] of inert gas synthesized nanoparticles, in the types of nanoparticles produced and qualitatively in their observance ratio. Our results strongly indicated that early stage coalescence (sintering) events and lower temperatures are the mainly responsible for the occurrence of the Dh and fcc based morphologies, while "ideal" atom by atom growth conditions produced the Ih morphology almost exclusively. These results provide a possible explanation as to why the Dh to Ih occurrence ratio increases as a function of nanoparticle size as observed by Koga and Sugawara. read less NOT USED (high confidence) G. Grochola, I. Snook, D. Chui, and S. Russo, “Exploring the effects of different immersion environments on the growth of gold nanostructures,” Molecular Simulation. 2006. link Times cited: 5 Abstract: Even though Au crystallizes only as a simple FCC structure i… read moreAbstract: Even though Au crystallizes only as a simple FCC structure in bulk there have been many different and fascinating structures discovered experimentally for Au on the nanoscale. Unfortunately, for Au a direct ab-initio approach in studying dynamic growth mechanisms of nanostructures is prohibitively expensive from a computational perspective, so here we use methods based on accurate semi-empirical, many-body potentials whose parameters are obtained from a combination of empirical and ab-initio data as a viable alternative. We show that this method when combined with molecular dynamics may be used to simulate the growth of Au particles in a bath of solvent atoms (either in a gaseous or liquid state) which results in structures of a range of different morphologies. An analysis of the results indicates what characteristics of the solvent and its interactions are important in determining these different morphologies. read less NOT USED (definite) K. Kolluri and M. Demkowicz, “Coarsening by network restructuring in model nanoporous gold,” Acta Materialia. 2011. link Times cited: 77 NOT USED (definite) T. Yamamoto, S. Ohnishi, Y. Chen, and S. Iwata, “Effective Interatomic Potentials Based on The First-Principles Material Database,” Data Sci. J. 2009. link Times cited: 0 Abstract: Effective interatomic potentials are frequently utilized for… read moreAbstract: Effective interatomic potentials are frequently utilized for large-scale simulations of materials. In this work, we generate an effective interatomic potential, with Niobium as an example, using the force-matching method derived from a material database which is created by the first-principle molecular dynamics. It is found that the potentials constructed in the present work are more transferable than other existing potential models. We further discuss how the first-principles material database should be organized for generation of additional potential. read less |
EAM_Dynamo_GrocholaRusso_2005_Au__MO_557267801129_000
