Anticorrugation in inelastic He-atom scattering from Rh(111) surfaces

Recent measurements supported by nb initio calculations have shown that the interaction of He atoms with transition metal surfaces is anticorrugating, i.e., the electron density seen by He is higher in the bridge positions than in the on-top positions. By shifting the electron charge density away from the atomic positions and using the Esbjerg-Norskov approach to determine the interaction potential, we evaluate the inelastic reflection coefficients of He with Rh(lll). The structure factor introduced by the anticorrugation explains, in a simple way, the high intensity observed for the resonant mode.