An experimental and theoretical investigation of the electronic structure of CdO

Photoemission spectra of polycrystalline CdO have been measured under excitation with monochromatic x-rays and with variable energy UV radiation from a synchrotron source. Experimental data are compared with density of states profiles calculated by periodic Hartree-Fock and density functional methods. Both calculations suggest that there is significant mixing between Cd 4d and O 2p states, but the Hartree-Fock calculations better reproduce the experimental O 2p to Cd 4d separation and the O 2p bandshape. Constant initial state profiles measured with variable photon energy in the range between 30 eV and 100 eV provide experimental evidence for O 2p-Cd 4d mixing.