Auger electron diffraction from NiO(100) layers on Ag(100)

NiO(100) films have been prepared by deposition of Ni onto Ag(100) in an O2 atmosphere. As deduced from low-energy electron diffraction and photoelectron spectroscopy the films are ordered and grow in a layer-by-layer mode. Auger electron diffraction of such films has been measured for the O (512 eV) and Ni (848 eV) Auger transitions in the entire halfspace above the sample surface by using a toroidal electrostatic energy analyzer. The results are compared with computations which have been obtained by multiple scattering cluster calculations including spherical wave corrections. The agreement between experimental and theoretical data is promising for the O transitions. For the Ni transitions we have found an unexpected intensity behavior which is tentatively ascribed to dominant contributions of inelastically scattered electrons.