First-principles calculations of the electronic band structure of In4Sn3O12 and In5SnSbO12

Abstract

The electronic band structures of M7O12 rhombohedral In4Sn3O12 and In5SnSbO12 are studied using the projector-augmented-wave method based upon the density-functional theory within the generalized gradient approximation. The cation ordering in both materials, as determined by means of ab initio self-consistent total-energy calculations, confirms the results of previous structural studies. It is found that the valence-band maximum states of these two materials are mainly formed by O 2p states hybridized with In 5d characters whereas the bottoms of conduction bands are due primarily to Sn 5s electrons at M2 sites. The present study shows that the introduction of antimony into In4Sn3O12 broadens the splitting of the conduction band, which is presumably related to the substantial change in electrical conductivity observed in In5SnSbO12.