Ab-initio computation of structural, elastic, mechanical and optical properties of Cs2ScAgI6 double perovskite semiconductor compound

Abstract

A novel Cs2ScAgI6 double perovskite semiconductor material has been investigated on electronic, mechanical, elastic and optical properties using the plane wave self-consistent field method by using generalised gradient approximation and Perdew–Burke–Ernzerhof as the exchange correlation functional. The material has an indirect bandgap of 2.06 eV as estimated by GGA–PBE, furthermore using HSE approximation, a bandgap of 2.99 eV was obtained. The states responsible for the electronic bandgap formation were Ag 3d, I 2p and Sc 3d for valence band, and Sc 3d, Sc 4 s and Cs 3 s for conduction band with other states contributing insignificantly. The material was found to be mechanically stable and ductile. The optical properties have revealed its suitability for photovoltaic applications.