Oxygen K x-ray-absorption near-edge structure of alkaline-earth-metal and 3d-transition-metal oxides.

Abstract

The oxygen K x-ray-absorption near-edge structure of alkaline-earth-metal and 3d-transition-metal oxides has been measured by means of the photoelectric yield method. The short-range order multiple scattering calculations for O K-edge spectra of CaO and TiO have also been performed. From comparison of the observed spectra with the calculated results, the effective cation charge is estimated with q=0.7 for CaO. In the case of 3d-transition-metal oxides, the calculated results are sensitive not only to the cation charge but also to the 3d electron number (d). For TiO, the effective cation charge and the number of 3d electrons are estimated with q=0.7--0.8 and d=1.8--2.0. .AE