CLOSE-COUPLING CALCULATIONS FOR ION-SURFACE INTERACTIONS

The time-dependent close-coupling equations for the ion-jellium-surfac e system are solved both by means of a fixed-ion self-energy formalism and by direct integration. The self-energies yield non-perturbative l evel shifts and widths, as well as information about the formation of hybrid orbitals in the combined potentials of ion and surface. Converg ence of the self-energy results is achieved within a small set of disc rete hydrogenic basis functions centered on the ion. In general, the c alculated level shifts and widths are in good agreement with the resul ts of other theoretical investigations. The direct time integration is applied in an exploratory study to the dynamics of hollow-atom format ion in surface interactions of highly charged ions.