Structural, Electronic, Elastic, and Optical Properties of Cubic BaLiX<sub>3</sub> (X = F, Cl, Br, or I) Perovskites: An <i>Ab-initio</i> DFT Study

This study reports for the first time theoretical prediction of structural, electronic, elastic and optical properties cubic BaLiCl3, BaLiBr3, BaLiI3 perovskites. The corresponding well-known BaLiF3 are also theoretically investigated. Density Functional Theory (DFT) using Generalized Gradient Approximation (GGA) was implemented within Quantum Espresso package to investigate results revealed that BaLiX3 (X = F, Cl, Br, I) in ionic crystal forms with optimized lattice parameters 4.04, 4.90, 5.21, 5.66 Å, respectively. minor band gaps were found be 6.62 eV (Γ→Γ), 4.29 (R→Γ), 3.50 2.58 (R→Γ) respective compounds. investigation their indicated these perovskites all mechanically stable, while only BaLiBr3 malleable. Finally, studied exhibit excellent properties, including low reflectivity high absorption ultraviolet region. Hence, it is predicted suitable various optoelectronic applications involving UV However, more favorable than BaLiCl3 deposited as thin films due flexibility.