| Property Definition (short name)
A common way to refer to the Property Definition. Note there may be multiple Property Definitions with the same short name, to fully distinguish between Property Definitions the full Tag URI must be used (the Property Definition ID).
| elastic-constants-isothermal-npt |
|---|---|
| Property Definition ID
The full Property Definition identifier using the Tag URI scheme.
| tag:staff@noreply.openkim.org,2024-07-10:property/elastic-constants-isothermal-npt |
| Title
A brief one-sentence description of this Property Definition.
| Isothermal elastic constants of a crystal at a given temperature and stress state |
| Description
A description about this Property Definition.
| The independent isothermal elastic constants of a crystal at a given temperature and stress state. The elastic constants are defined as the 2nd derivatives of the strain energy density with respect to the infinitesimal strain tensor. The structure of the crystal is expressed as an AFLOW prototype label and its corresponding free parameters representing the average positions of the constituent atoms. |
| Contributor
The user or organization who initially contributed this Property Definition.
| ilia |
| Maintainer
The user or organization who currently maintains this Property Definition.
| ilia |
| Creation date
The date the Property Definition was "minted", based on its Tag URI.
| 2024-07-10 |
| Content on GitHub
The following content may be available on GitHub: Property Definition (an EDN file containing the Property Definition Keys listed below); Physics Validator (a script provided by the user for validating that an instance of the Property is physically valid); Property Documentation Wiki (the contents of the Wiki displayed at the bottom of this page).
|
Property Definition Physics Validator Property Documentation Wiki |
| type | float |
|---|---|
| has-unit | true |
| extent | [] |
| required | true |
| description | The average 'a' lattice constant of the crystal structure as defined by the AFLOW standard. Relative values of other lattice parameters (if present) are given in the 'parameter-values' key. |
| type | float |
|---|---|
| has-unit | true |
| extent | [6] |
| required | true |
| description | The [xx,yy,zz,yz,xz,xy] components of the symmetric Cauchy stress tensor at the reference configuration at which the elasticity tensor is evaluated. The components should be expressed in the same coordinate system as the structure specified by prototype-label and parameter-values, with the orientation of lattice vectors defined in M. J. Mehl et al., Comput. Mater. Sci. 136, S1 (2017). |
| type | string |
|---|---|
| has-unit | false |
| extent | [":"] |
| required | true |
| description | Names of the unique elastic constants of the crystal system to which the crystal belongs. They are expressed in Voigt notation with the order [xx,yy,zz,yz,xz,xy]. The components should be expressed in the same coordinate system as the structure specified by the prototype-label and parameter-values, with the orientation of lattice vectors defined in M. J. Mehl et al., Comput. Mater. Sci. 136, S1 (2017). |
| type | float |
|---|---|
| has-unit | true |
| extent | [":"] |
| required | true |
| description | Values for the elastic tensor components listed in 'elastic-constants-names'. |
| type | float |
|---|---|
| has-unit | true |
| extent | [6 6] |
| required | true |
| description | The elasticity matrix in Voigt notation with the order [xx,yy,zz,yz,xz,xy]. It is guaranteed to obey the symmetry of the described crystal. If the elastic constants were not computed or measured using a procedure that is inherently symmetry reduced, this is computed from 'elasticity-matrix-raw' by algebraically correcting to enforce the crystal symmetry. |
| type | string |
|---|---|
| has-unit | false |
| extent | [] |
| required | true |
| description | Prototype label (not including an enumeration suffix) as defined by the AFLOW standard (e.g. 'A_tI4_141_a') for the structure. It is expected that the alphabetically lowest of all equivalent labels is chosen. |
| type | string |
|---|---|
| has-unit | false |
| extent | [":"] |
| required | true |
| description | Element symbols corresponding to the atom types in the stoichiometric formula which appears at the start of the prototype label (e.g. ['Mo','S'] for the AB2 stoichiometric formula, means that the 'A' atom is 'Mo' and the 'B' atom is 'S' for the MoS_2 structure). |
| type | float |
|---|---|
| has-unit | true |
| extent | [] |
| required | true |
| description | Temperature of the crystal. |
| type | file |
|---|---|
| has-unit | false |
| extent | [] |
| required | false |
| description | A file containing the atomic configuration including information such as the species, x,y,z coordinates of each particle, and periodicity data. |
| type | string |
|---|---|
| has-unit | false |
| extent | [":"] |
| required | false |
| description | The identifier (ID) of the Crystal Genome (CG) structure for which the property (test result and instance) containing this key was computed. The ID points to an archived CG structure (test result and instance) and has the following format: '[KIM test result uuid]:[instance-id]', e.g., 'TE_258644009221_002-and-MO_751354403791_005-1715722494-tr:2'. |
| type | float |
|---|---|
| has-unit | false |
| extent | [] |
| required | false |
| description | The distance between the elasticity tensor to the nearest matrix of elastic constants for an isotropic material expressed in the log Euclidean metric. See Morin, L et al., J. Elast., 138, 221 (2020). |
| type | float |
|---|---|
| has-unit | true |
| extent | [6 6] |
| required | false |
| description | The elasticity matrix in Voigt notation with the order [xx,yy,zz,yz,xz,xy]. This is provided if the elastic constants were computed or measured in a non-symmetry-reduced fashion. Due to numerical or experimental errors, this matrix may not satisfy expected symmetries exactly. Symmetrized results are provided in 'elasticity-matrix'. |
| type | string |
|---|---|
| has-unit | false |
| extent | [] |
| required | false |
| description | The AFLOW library prototype, if any, matching the structure. Prototypes in the AFLOW library are associated with common short names used by the materials community. The library prototype includes an integer enumeration suffix defined by the AFLOW standard when there are multiple parameter values associated with the structure (e.g. 'A_tI4_141_a-001' for 'betaSn'). Because these prototype labels are named according to their original material's conventional chemical formula, they may differ from the 'prototype-label' key, which is expected to be standardized to have the alphabetically lowest possible of all equivalent labels. |
| type | string |
|---|---|
| has-unit | false |
| extent | [":"] |
| required | false |
| description | Names of the parameters other than 'a', if present, corresponding to this AFLOW prototype. These can include lattice parameters from the set {'b/a','c/a','alpha','beta','gamma'} (for the conventional crystal structure defined by lattice parameters a, b, and c and angles alpha, beta, gamma), and coordinates of Wyckoff positions that have a degree of variability labeled as 'x*', 'y*' and 'z*' where the asterisk represents an integer as defined by the AFLOW standard. |
| type | float |
|---|---|
| has-unit | false |
| extent | [":"] |
| required | false |
| description | Values for the parameters listed in 'parameter-names' corresponding to the average positions of the atoms. Note that all parameters are dimensionless. |
| type | string |
|---|---|
| has-unit | false |
| extent | [":"] |
| required | false |
| description | Commonly used name associated with the 'library-prototype-label' key according to the AFLOW prototype library (e.g. 'Face-Centered Cubic' or 'Molybdenite'). |