Initial and final state effects in the ESCA spectra of cadmium and silver oxides

The factors which influence chemical shifts are examined in order to elucidate the cause of the anomalous chemical shifts for Cd and Ag oxides. The effects of extra-atomic relaxation are accounted for using a procedure employing experimental Auger and binding energies. Atomic partial ionic charges for some simple Cd, Ag, and Zn compounds are calculated from experimental binding energies using a model which includes the effects of lattice potentials and extra-atomic relaxation. Inclusion of extra-atomic relaxation effects did not have a drastic effect on the relative ionicities computed for these selected compounds. However, for CdO, a large extra-atomic relaxation energy contribution reduces the binding energy by 0.5 eV more than is predicted from nearest neighbor electronegativity arguments.