Computation of the thermal elastic constants for arbitrary manybody potentials in LAMMPS using the stress-fluctuation formalism

This paper describes the implementation of the stress-fluctuation technique into the LAMMPS code to compute the anisotropic thermal elastic constants tensor of materials. The implementation provides both methods for computing the analytical fluctuation expressions and also a generic numerical deriva...

Full description

Saved in:
Bibliographic Details
Published in:Computer physics communications 2023-05, Vol.286 (C), p.108674, Article 108674
Main Authors: Clavier, Germain, Thompson, Aidan P.
Format: Article
Language:English
Subjects:
Computer Science
Elastic constants
LAMMPS
Modeling and Simulation
Molecular simulation
Physics
Stress-stress fluctuations
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This paper describes the implementation of the stress-fluctuation technique into the LAMMPS code to compute the anisotropic thermal elastic constants tensor of materials. The implementation provides both methods for computing the analytical fluctuation expressions and also a generic numerical derivative method. The former makes the extension to new potentials straightforward, as it requires writing code only for the second derivatives of each energy term w.r.t. distance, angle, etc. The latter provides a generic interface to compute an accurate approximation of the elastic constants for any potential already implemented in LAMMPS. We show how both methods compare with the direct deformation computation in several test cases and discuss the implementation advantages and limitations.
ISSN:0010-4655
1879-2944
DOI:10.1016/j.cpc.2023.108674