First-principles calculations of the electronic structure and Mِssbauer parameters of Sb-doped

The electronic structure and the 119Sn and121Sb Mِssbauer parameters of Sb-doped SnO2 were calculated using a first-principles method. We show that substitution of Sn by Sb leads to a small decrease of the distances between the dopant and the six oxygen first-nearest neighbours. The most important modifications in the electronic structure are related to the bottom of the conduction band, which has Sb 5s, Sn 5s and O 2p characters. By considering two supercell sizes and charged supercells we show that antimony oxidation state is Sb5+ and we explain the origin of the Mِssbauer parameters from the local electronic structure of the cations.