First principle study of structural and optoelectronic properties of ZnLiX3 (X = Cl or F) perovskites

Abstract

The zinc-based perovskites ZnLiX₃ (X = Cl or F) were investigated for their structural, electronic, and optical properties using the WIEN2k package within density functional theory (DFT). Structural properties were calculated using the generalized gradient approximation (GGA), while the modified Becke-Johnson (mBJ) potential was applied for a more accurate description of the optical and electronic properties. Both compounds are confirmed to be stable, crystallizing in the cubic Pm-3 m (No. 221) space group. ZnLiCl₃ has an indirect band gap of 0.30 eV between the Γ and M symmetry points, indicating semiconducting behaviour, while ZnLiF₃ exhibits an indirect band gap of 5.45 eV, typical of an insulating material. The electronic states contributing to the band structure were analyzed using the total density of states (TDOS) and partial density of states (PDOS). Optical properties, evaluated in the energy range of 0–14 eV, reveal strong optical conductivity and absorption at higher energies, while both materials show transparency to lower-energy photons. These findings suggest that ZnLiCl₃ and ZnLiF₃ are suitable candidates for high-frequency UV optoelectronic device applications.