Abstract

This paper is concerned with stress and strain fields at atomic scale. Unlike other formulations of atomistic expression of macroscopic stress fields or homogeneous systems, this paper aims at field descriptions of atomic stresses and strains for multi-element crystalline materials. By decomposing atomic deformation into homogeneous lattice deformation and inhomogeneous relative atomic deformation, a field representation of momentum flux is formulated within the framework of atomic many-body dynamics, and the connection to a macroscopic definition of stress is obtained. The atomic strain measures and the atomic stress-strain relations are derived. Phonon dispersion relations are calculated and presented.

Keywords

stress, strain, atomic scale, many-body dynamics

Authors