Computer modelling of pure and doped titanium dioxide in anatase structure

Abstract

The structural, electronic and optical properties of titanium dioxide (TiO2) in anatase phase have been studied by first-principle self-consistent local density approximation. Norm-conserving pseudopotentials were utilized and wavefunctions were represented by using plane wave basis set. Calculated structural parameters of anatase within LDA agree well with the experimental parameters. Optimized atomic positions of TiO2 are the same as the original positions. Densities of states were calculated and they are instructive to the understanding of the system. Pressure dependence structure shows high compressibility along the c parameter. The bulk modulus of TiO2 was calculated and was found to be 178.9 GPa which agrees well with the experimental value which is 179.0 GPa. We have doped anatase with transition metals (Pt, Au, Ag and Pd) to study their effect on structural and optical properties of TiO2. Doping decreases the band gap of the structure and increases the optical properties (absorption and reflectivity) of pure anatase in the visible region.