The charge-density distribution in V2O3 differs from that in Ti2O3 mainly with respect to the deformation of the metal atoms. The V atoms show a positive deformation of up to 0.1 e Å-3 perpendicular to c in a plane containing three nearest V-atom sites across the edges of the surrounding O-atom octhedra, and a negative deformation of up to 0.3 e Å-3 parallel to c between the nearest V-atom site across the faces of the O-atom octahedra. These observations are in accordance with theoretical band-structure calculations and confirm the existence of an e metal-metal bond which is directed across the common edges of the metal-centered O-atom octahedra.
Vincent, M. G., Yvon, K. and Ashkenazi, J. (1980), Electron-density studies of metal–metal bonds. II. The deformation density of V2 O3 at 295 K. Acta Crystallographica Section A, 36: 808–813. doi: 10.1107/S0567739480013101