Electronic structure of VO2 studied by x-ray photoelectron and x-ray emission spectroscopies

A VO2 single crystal has been the subject of a combined investigation by high-resolution x-ray photoelectron spectroscopy (XPS), x-ray emission spectroscopy (XES) with both electron and energy-selective x-ray excitation (V L alpha, V K beta(5) and O K alpha emission) and x-ray absorption spectroscopy (XAS) (O Is). We performed first-principles tight-binding LMTO band-structure calculations for VO2 in both the monoclinic and tetragonal rutile phases and compared the densities of states (DOS) with the experimental data. From this we conclude that the electronic structure of VO2 is more bandlike than correlated.