HYBRIDIZATION OF IONIC LEVELS AT METAL-SURFACES

We investigated the hybridization of He+, Li2+, and Be3+ ionic levels and the creation of surface resonances for nuclear charges Z=2, 3, and 4 near an Al surface. Starting from a two-center basis set expansion with hydrogenic wave functions on the ion site and jellium wave functi ons in the metal half space, we calculate the self-energy for ion-surf ace system in the fixed-ion approximation. We obtain convergence by us ing a rather small set of bound ionic states. This ideally suits this method for the generation of adiabatic basis states that can be used i n time-dependent close-coupling calculations for slow ion-surface coll isions. We compare our resonance energies and widths with other theore tical approaches, discuss electronic density profiles, and analyze res onances in terms of Stark states.