Charge exchange in atom-surface scattering and sputtering processes

A Green function analysis of the charge transfer probability for an atom scattered by a semi-infinite linear chain is performed within the one-particle Anderson-Newns model. The main intervening ingredients are the finite but continuous limit of the substrate bandwidth and the eventual presence of surface states. The dependence on the velocity of the moving atom, as well as the effects of including surface states, are comparatively discussed.