Figure 1From: First-principles study on transition metal-doped anatase TiO2Models for calculation. (a) Unit cell of anatase TiO2; (b) Structure of 2 × 1 × 1 supercell model of transition metal-doped TiO2. The gray spheres, the red spheres, and the blue sphere represent Ti atoms, O atoms, and transition metal atom, respectively.Back to article page