A Green's function approach to deriving non-reflecting boundary conditions in molecular dynamics simulations

Computer simulations of atomic scale processes in solids are often associated with the issue of spurious reflection of elastic waves at the boundaries of a molecular dynamics domain. In this paper, we propose an approach to emulate non-reflecting boundary conditions in atomistic simulations of crystalline solids. Harmonic response of the outer, non-simulated, region is accurately represented by a memory function, related to the lattice dynamics Green's function. The outward wave flow is cancelled due to work done by the corresponding response forces. Performance of method, dependent on a series of method parameters, is illustrated on a benchmark problem.