X-Ray Photoelectron Band Structure of Some Transition-Metal Compounds

The valence-band structures of MnO, CoO, NiO, CuO, ${\mathrm{Cu}}_2$O, Ni${\mathrm{Cl}}_2$, NiS, and KNi${\mathrm{F}}_3$ have been obtained by x-ray photoelectron spectroscopy. Band widths and positions are obtained, and are compared with the results of band-structure calculations. Bandwidths for the oxides are in accord with augmented-plane-wave calculations. Bands positions are better described by shifting free-ion energy levels according to the Madelung energy. The structure of the $d$ band of NiO is compared with other experimental and theoretical results.