Structural, electronic, and optical properties of rare-earth-doped SrTiO3 perovskite: A first-principles study

The doping effect of the addition of rare earth elements (Pr, Nd, and Sm) on the mechanical and dielectric properties of the strontium titanate perovskite SrTiO3 was investigated using density functional theory (DFT). The introduction of rare earth elements modifies the structural properties and the charge distribution. Distortion of the Ti–O6 octahedron results in a decreasing trend in the mechanical and electronic properties with increasing nuclear charge numbers of Pr (59), Nd (60), and Sm (62). Rare earth element substitutions move the Fermi-level into the conduction band and change the absorption spectrum by adding peaks at 0.1–0.4 eV.