The study on the electronic structure and optical properties of stressed OsSi<sub>2</sub>

Abstract

A detailed theoretical study of electronic structure, density of states and optical properties of OsSi₂ under isotropic lattice deformation was performed by means of first-principles pseudopotential method. It was found that the isotropic lattice deformation results in the decrease in the energy gap from 96% lattice to 104% lattice. When the crystal lattice is 96% compressed, the indirect band gap is 0.928 eV; 104% stretched, the indirect band gap is 0.068 eV. Furthermore, the curve of optical properties tend to low-energy direction, When the crystal lattice is stretched, the static dielectric function increases; when compressed, the absorption enhances, and then improves the photoelectric conversion efficiency.