First-Principles Calculations of Structural, Elastic and Electronic Properties of Cubic CsBeI3 Compound

The structural, elastic, and electronic properties of the cubic CsBeI3 compound have been calculated using the full potential linearized augmented plane wave (FP-LAPW) method based on density functional theory (DFT). The exchange–correlation potential for structural and elastic properties has been evaluated using the generalized gradient approximation (GGA-PBE), while the modified Becke-Johnson potential (mBJ-GGA) has been employed in the calculation of the band structure. The structural parameters (lattice constant and bulk modulus) were found to be in reasonable agreement with the available data. Additionally, the elastic constants (C11, C12, and C44), elastic moduli and Debye temperature have been studied for the first time. We have predicted the electronic band structure and density of states, and CsBeI3 exhibits semiconductor behavior with an indirect band gap of 0.4628 eV. The upper valence bands are essentially dominated by I-p states. The estimated elastic parameters of this material indicate that it is anisotropic, ductile in nature, and mechanically stable.