First-Principles Study of Titanium Dioxide: Rutile and Anatase

The atomic and electronic structures of two phases of titanium dioxide, anatase and rutile, have been investigated by a first-principles pseudopotential method based on local density approximation in density functional theory. The calculated band structure, equilibrium lattice constants, and bulk modulus of rutile are consistent with experimental data and with other calculations. The calculated structure of anatase is also close to experimental data. The calculated bulk modulus of anatase is found to be smaller than that 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 energetics between the two phases is also discussed.