Ab-initio study of the structural, electronic, optical, and mechanical properties of the ternary compounds ABSe3 (A = Cs, Tl)

Abstract

In this research, we examined the ternary ABSe3 compounds' structural, elastic, optical, and electrical characteristics. These compounds form monoclinic crystals. By handling the energy of exchange and correlation by the approximation of the generalized gradient PBE, we employed the abinitio calculation approach, which is that of the density functional theory (DFT) framework and implemented in the CRYSTAL code and CASTEP code. Using Voigt, Russ, and Hill approximations, we approximated the bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and other isotropic elastic moduli and associated characteristics for single crystal and polycrystalline phases using these numerical values obtained from the Cijs. Since we checked the mechanical stabilities of Cijs using numerical data. We also briefly covered the optical characteristics, total and partial electronic density diagrams (TDOS and PDOS), band structure, and other electronic features.