Molecular dynamics simulations of homogeneous solids using multi-layered structures

Abstract

The main goal of this work is to model a homogeneous computer material with well-defined mechanical properties. To carry out the model material, an internal structure arranged in layers with different atom sizes is implemented using a simple interatomic law of Lennard-Jones type (LJ). We show that imposing an appropriate scaling law between the interatomic potentials from different layers, we obtain the same mechanical properties as if the material was homogeneous. Employing this scheme, given a fixed space volume to be occupied by the solid, this structural arrangement allows to decrease drastically (∼30-80%) the required number of atoms as compared with the case of a homogeneous solid, decreasing the computational effort and speeding up calculations. In that respect, this procedure is an analogous to mesh refinements methodologies usually applied in the continuum approaches.