Electronic and structural properties of Sr 2YSbO 6

Abstract

The electronic and structural properties of the cubic perovskite Sr 2YSbO 6 were predicted from ab initio calculations. Such properties were obtained using the density functional theory (DFT). The full-potential (linearized) augmented plane-wave ((L)APW) method was used, as it is implemented in wien2k code. We have optimized the volume of the unitary cell and the internal x parameter. The lattice constant ( a ) and x determine some length bonds. We have found that a = 8.405 Å, x = 0.26177 , and the bond lengths Y–O and Sb–O are 2.20 and 2.00 Å, respectively. Additionally, Sr 2YSbO 6 was prepared experimentally by the solid-state reaction method using stoichiometric mixtures of high purity (99.99%). By means of X-ray and Rietveld analysis, the main structural features were determined. The experimental lattice parameter is a = 8.249 Å, which differs about 1.9% of the value obtained using DFT. The bulk modulus is ∼ 133 GPa, which is not measured experimentally. DFT predicts that Sr 2YSbO 6 is an indirect semiconductor and magnetic behavior does not have to be expected because at Fermi level the dominant orbitals are p-oxygen. The gap of the material is at least 2.5 eV.