New article on "A force-matching Stillinger-Weber potential for MoS2: Parameterization and Fisher information theory based sensitivity analysis" published in J. Appl. Phys.

22-Dec-2017

A new article titled "A force-matching Stillinger-Weber potential for MoS2: Parameterization and Fisher information theory based sensitivity analysis" by Mingjian Wen, Sharmila N. Shirodkar, Petr Plechac, Efthimios Kaxiras, Ryan S. Elliott and Ellad B. Tadmor has been published in the Journal of Applied Physics. The article describes a new Stillinger-Weber type potential for 2D MoS2. The uncertainty in the potential parameters is determined using a Fisher information theory analysis. The model driver for this potential is available here.

From the abstract:

"Two-dimensional molybdenum disulfide (MoS2) is a promising material for the next generation of switchable transistors and photodetectors. In order to perform large-scale molecular simulations of the mechanical and thermal behavior of MoS2-based devices, an accurate interatomic potential is required. To this end, we have developed a Stillinger-Weber potential for monolayer MoS2. The potential parameters are optimized to reproduce the geometry (bond lengths and bond angles) of MoS2 in its equilibrium state and to match as closely as possible the forces acting on the atoms along a dynamical trajectory obtained from ab initio molecular dynamics. Verification calculations indicate that the new potential accurately predicts important material properties including the strain dependence of the cohesive energy, the elastic constants, and the linear thermal expansion coefficient. The uncertainty in the potential parameters is determined using a Fisher information theory analysis. It is found that the parameters are fully identified, and none are redundant. In addition, the Fisher information matrix provides uncertainty bounds for predictions of the potential for new properties. As an example, bounds on the average vibrational thickness of a MoS2 monolayer at finite temperature are computed and found to be consistent with the results from a molecular dynamics simulation. The new potential is available through the OpenKIM interatomic potential repository at https://openkim.org/cite/MO_201919462778_000."

The full article is available here.