First principles study of the structural and optoelectronic properties of the A2InSbO6 (AÂ =Â Ca, Sr, Ba) compounds

Different physical properties of the double perovskite A2InSbO6 (A = Ca, Sr, Ba) compounds are investigated using the full potential linear augmented plane wave method within the density functional theory (DFT) where different generalized gradient approximations are used for approximating the exchange-correlation effects. Importantly, the DFT calculated structural indexes are in close agreement with the experimental data. The compounds show a semiconductor nature with a direct bandgap where the upper valence band is mainly consist of the O-p state, and the lower part of the conduction band is composed of the Sb-s state. Furthermore, the electron charge density plots show that the chemical bonding is partially covalent and ionic. From the DFT calculated optical properties, it is clear that the A2InSbO6 (A = Ca, Sr, Ba) compounds strongly absorb and reflect the incident radiation in the visible and ultraviolet range and can therefore be effectively used in optoelectronic devices .