Electronic, optical, and transport properties of alkali metal oxides (Cs2O): A DFT study

Abstract: The electronic, structural, optical, and thermoelectric properties of the Cs2O cubic structure have been investigated using density functional theory (DFT). The calculations utilize a full relativistic version of the full-potential augmented plane-wave plus local orbitals method, which is based on density functional theory, employing both the GGA and LDA approximations. Additionally, we employed the GGA proposed by Trans-Blaha (GGA-mBJ) for band structure computations, revealing the indirect band gap nature of Cs2O. The optical properties are also addressed by computing the refractive index, extinction coefficient, and complex dielectric tensor. The electrical conductivity, Seebeck coefficient, and thermal conductivity exhibit temperature-dependent variations, indicating the formation of a thermoelectric material. Our findings indicate that the compound under investigation is categorized as a p-type semiconductor, with the majority of charge carriers responsible for conduction being holes rather than electrons.