Electronic Absorption Spectra of V(2)O(5)

MO calculations of electronic structure and optical transitions for [VO(n)](5.2n) ( n = 4,5,6) clusters in V(2)O(5) monocrystals have been carried out by means of the semiempirical CNDO CI method. Using the calculated results, a complete analysis of V(2)O(5) optical data as available in the literature and as obtained in the electroreflectivity experiments presented in this paper is performed. An identification of optical transitions in a wide energy range is presented. The optical properties of vanadium pentoxide are shown to be due to the localized charge transfer electronic transitions in the clusters. The fine structure of optical spectra is connected with the covalent splittings of the vanadium 3d and oxygen 2 p atomic levels.