keV particle bombardment of solids: molecular dynamics simulations and beyond

The bombardment of solids with keV atoms or ions leads to rather violent collisions with subsequent ejection of target particles. This review discusses computational aspects of molecular dynamics simulations designed to describe this process, and presents studies in which the calculations have played an important role in understanding the details of the bombardment and ejection processes at the atomic level. The molecular dynamics simulations in conjunction with comparable experiments allow this process to be used as a measure of surface structure. Recently experiments were performed that measured the energy and angular distributions of particles ejected in two electronic states. We have accordingly incorporated a simple electronic excitation/de-excitation model into the simulation and shown that collisional events are important to describe the measured distributions.