First-principles study of titanium dioxide: Rutile and anatase

The atomic and electronic structures of two phases of titanium dioxide, ana tase and rutile, have been investigated by a first-principles pseudopotenti al method based on local density approximation in density functional theory . The calculated band structure, equilibrium lattice constants, and bulk mo dulus of rutile are consistent with experimental data and with other calcul ations. The calculated structure of anatase is also close to experimental d ata. The calculated bulk modulus of anatase is found to be smaller than tha t of rutile, presumably due to the sparsity of anatase. The band structure of anatase is given in comparison with that found in previous works. The en ergetics between the two phases is also discussed.