Structural, electronic and optical properties of double perovskite oxide BaSrMgTeO6

A double perovskite BaSrMgTeO6 has been synthesized and characterized by physical techniques: X‐ray diffraction, and diffuse reflectance spectroscopy. It crystallizes at room temperature, in the cubic system with unit cell parameters: a=8.018Å (S.G Fm‐3m) and shows an almost perfect ordering between Mg2+ and Te6+ cations at the B substructure. Based on Density Functional Theory (DFT), and using full Potential‐linearized Augmented Plane Wave (FPLAPW) method with the Generalized Gradient Approximation (GGA), implemented in the Wien2k package, we have investigated electronic and optical properties of such material. The optical band gap obtained with GGA approximation is equal to 2.8 eV, which is in good agreement with our experimental results. We found that transmittance T is stable and reaches the average of 90% in both experimental and theoretical studies.