Avoiding Defect Nucleation during Equilibration in Molecular Dynamics Simulations with ReaxFF

Abstract : Classical molecular dynamics simulations typically require an initial equilibration phase to obtain a suitable starting configuration at the desired temperature and pressure. We have observed in various simulations of molecular crystals that, in some instances, defects spontaneously form when the reactive force field ReaxFF-lg is used. The source of defect formation is attributed to improper equilibration of the system. This technical note describes an alternate equilibration method that results in a defect-free crystal after equilibration.