Analysis of the X-ray photoelectron spectra of transition metal compounds using approximate molecular orbital theories

Abstract

The application of approximate molecular orbital calculations within the framework of the charge potential model to the analysis of X-ray photoelectron spectroscopic binding energies is evaluated. Most of the calculations and experimental data refer to chromium compounds. The approximate molecular orbital calculations used are CNDO, extended Hückel, and charge iterated extended Hückel (using both CNDO and gross atomic charges). Calculations are carried out using both the ground and relaxation potential models (GPM and RPM). The results suggest that the CNDO charges in the RPM model provide the best agreement with experiment.