Ion neutralization near a contaminated metal surface

Abstract The ion neutralization near the surface of a contaminated metal is investigated within the framework of the approximate many-level method. Calculations show that the electronic structure and the component of the substrate surface, by introducing the surface density of states and the impurity atom, play an important role in the ion resonance charge transfer. When the impurity is located in the surface, the impinging ion can be neutralized by picking up an electron from the localized impurity state. When the impurity moves into the substrate for several layers from the surface, the ion is mostly likely neutralized by the electrons from the band states, the corresponding ion-orbital occupancy is different when the impurity site changes. The effects of impurity on the surface-ion neutralization decrease as the impurity site moves away from the surface. The model is applied to the scattering of a Li + ion from a Ni(Cu)-contaminated substrate surface.