A new directional model for the electronic frictional forces in molecular dynamics simulations of radiation damage in metals

摘要: Abstract The damage caused by collision cascades in irradiated materials forms the initial conditions for longer term microstructural evolution. exchange of energy between electrons and ions during can significantly affect this damage. Models incorporating within classical molecular dynamics (MDs) simulations exist, but most approximate ion–electron transfer via a damping force, opposed to ionic motion. Although such forces predict total over duration cascades, they do not capture complex dependence non-conservative electronic friction force on speed, direction atomic environment individual ions. Here we present new model derived from quantum–classical Ehrenfest dynamics, which captures complexity is suitable inclusion existing MD codes at near-zero computational cost. We show that our reproduces level detail time-dependent tight-binding cascades.