Theory of the low-energy surface Okorokov excitation for studying excited states of atoms in collision with surfaces

A theory of the low-energy surface Okorokov excitation is presented and a new spectroscopy is proposed in which an atomic or ionic beam in collision with the surface at grazing incidence is excited electronically by a corrugated surface potential (Okorokov excitation). By monitoring ions and excited atoms in the specularly reflected beam, information about the shift and broadening of the atomic energy levels near the surface is obtained. We demonstrate ion and excited atom spectra in a suitable model. © 1988.