Inelastic processes in keV H + and He + scattering from Cu(110)

Abstract

Measurements and calculations for the kinetic electron emission from keV protons and He + ions grazingly incident on Cu(110) are discussed. The electron energy distributions are shown to be dominated by the emission of the localized 3d electrons of Cu during the atom-atom collisions at the surface. This mechanism gives rise to inelastic energy losses of the projectiles; the excitation of the 3d electrons of Cu to energies just above the Fermi level are shown to contribute significantly to the total energy loss. In case of H it is shown that also the contribution of the excitation of the 1s electron of H may be important. In case of He this is not the case due to the larger binding energies of the 1s electrons.