Band structures of nonmagnetic transition-metal oxides: PdO and PtO

The electronic band structures of PdO and PtO are calculated using the augmented-spherical-wave method and the local-density approximation. Our results are consistent with the widely held view of these materials as conventional band insulators with the crystal-field splitting of metal d states primarily responsible for gap formation. A significant role for correlation effects as well cannot be ruled out. The predicted valence-band structure for PdO agrees well with published photoemission data. The electronic structure of PtO is qualitatively similar. In both cases the calculated gap is direct and occurs at the M point of the Brillouin zone. The magnitude of the gap is found to be larger in PtO, which we attribute to the more relativistic nature of Pt compared to Pd.