The electronic structure of the vanadium dioxide VO2 in the tetragonal R and two monoclinic M1 and M2 structural modifications was determined by the local-density functional (LDA) method and the LSDA + U formalism of correction for correlation effects. Based on the results of calculation, we argue in favor of the Mott-Hubbard mechanism of the metal-insulator transition. It is shown that the transition is accompanied by the change of the orbital in which the 3d1 electron of the V4+ ion is localized. The symmetry of the filled orbital is determined by the local oxygen environment of the vanadium atoms in each structural phase. Depending on the dispersion of the band that corresponds to the orbital occupied, the investigated compound can be either a metal or an insulator.
|Number of pages||7|
|Journal||Physics of Metals and Metallography|
|Publication status||Published - Jul 2002|