Feature Activated Molecular Dynamics: Parallelization and Application to Systems with Globally Varying Mechanical Fields

Abstract

A recently developed hybrid molecular dynamics method (Feature Activated Molecular Dynamics, or FAMD), which was originally designed to extend the scope of certain types of molecular dynamics simulations, is extended here in two ways. First, the method is modified to execute on parallel computer architectures using the MPI communication interface. The parallel FAMD algorithm is demonstrated to be computationally efficient and to substantially increase the length scales accessible with molecular dynamics. The performance of the parallel algorithm is demonstrated using a crystalline system containing 1 × 10 6 atoms, in which 1000 supersaturated self-interstitials are introduced and allowed to aggregate for about 4 ns. In the second part of this paper, the FAMD method is applied to problems in which spatio-temporally varying stress fields are present throughout the simulation cell. In particular, we consider the evolution of a spherical void in a hydrostatically stressed silicon crystal and show that the method can capture the extremely rapid void cavitation dynamics following material failure. Once again, the FAMD approach is demonstrated to provide substantial computational advantages over standard molecular dynamics.

Photosensitive oxide semiconductors for solar hydrogen fuel and water disinfection

“…[70][71][72][73][74][75] As a consequence, these methods can be used to guide the selection of elements to be added to POSs as solid solutions.…”

“…Computational methods can be used to predict effects such as a tendency of certain lattice species to segregate to the surface, the resulting enrichment of the surface layer and the effect of that enrichment on the local properties. [70][71][72][73][74][75] As a consequence, these methods can be used to guide the selection of elements to be added to POSs as solid solutions.…”