Structural Stability and Electronic Properties of the I41/amd Vanadium Dioxide

By using LDA+U approach based on the density functional theory, the structural stability of I4(1)/amd VO2 is investigated. According to the phonon dispersion and stability criteria, the I4(1)/amd is suggested to be another possible and stable structure for the VO2. Lattice parameters of the I4(1)/amd VO2 are determined by geometry optimization. The energy band structure shows that the I4(1)/amd VO2 should be a metal. Furthermore, the upper valence band has dominant 2p-orbital characters, but the lower conduction band shows distinctive 3d-orbital characters. Obvious hybridization between the O-2p and V-3d orbitals is observed.