Semiclassical perturbation theory for atom scattering from surfaces with defects

Presented here is an extension of semiclassical perturbation theory (SCP) to gas-surface scattering incorporating surface defect sites with the restriction that the defects be diffuse enough such that they have no direct interaction. The formalism is applied to a corrugated surface with atoms missing, modeling a nearly complete layer of atoms adsorbed on a metal surface. The results show the redistribution of the Bragg intensities to a continuum of momentum transfers about the former peaks.