Abstract：Computations for electronic structures and optical properties of Ta doped anatase TiO₂ were carried out by first principle plane wave ultra-soft pseudo potential method based on the density functional theory. The results indicate that the impurity levels mixed with the bottom of conduction band and the forbidden band width decrease obviously after Ta atoms are doped in anatase TiO₂crystal. Both the introduction of impurity levels and the decreasing of band gap lead to the obvious absorption enhancement in the visible region for the Ta doped anatase TiO₂.

Keywords：doping; anatase; first principle