Structure relations in the x-ray photoelectron spectra of three chromium compounds

Abstract

The chemical shift in electron binding energy, magnetic splitting of electron shells, and structures in the valence band are examined for chromium in the 3 + and 6 + oxidation states. The splitting of the Cr 3 s energy level is associated with the appearance of a sharp Cr 3 d line in the valence band. The relative chemical shift in the Cr 2 p 3 2 line between Cr 2O 3 and K 2Cr 2O 7 is verified in the mixed compound KCr 3O 8 which contains both types of Cr ions, and the structure of this compound is verified by the X-ray photoelectron spectra. The spin-orbit intensity ratio of the 2 p doublet of Cr 6+ is 3, instead of the theoretical value of 2, and the spin-orbit splitting is less than for Cr 3+. In the 3 p level of Cr the relative chemical shift is 3.5 eV whereas for the 2 p 3 2 level the shift is only 2.4 eV. The differences in chemical shift and intensity ratio can not be explained.