Step effects in the interaction of highly charged ions (HCI) with a metal surface

We report on surface scattering experiments of 75 keV N5+ ions interacting with a single-crystalline Pt(1 1 0)(1 x 2) surface. We use grazing incidence conditions, i.e. the energy perpendicular to the surface is low enough to prevent penetration through the first atomic layers. Incident, azimuthal and scattering angle are varied. We investigate surface step effects by measuring the energy loss and the spatial intensity distribution of the scattered ions. The increase of energy loss with increasing scattering angle is partly attributed to step effects