First-principles calculation of the electronic structure, optical, elastic and thermodynamic properties of cubic perovskite LiBeF₃

Abstract

The elastic, electronic structure, optical and thermodynamic properties of cubic fluoroperovskite crystal LiBeF3 were investigated using the ab initio method. The calculated lattice parameter, elastic constants Cij, bulk modulus B and shear modulus G at 0 GPa and 0 K are agreed well with previous reports. The obtained band structure shows that LiBeF3 has an indirect energy band gap of 7.64 eV, which is consistent with the known results. Then, the dielectric function, absorption coefficient, and refractive index were investigated. It was found that the absorption part of LiBeF3 is located at the ultraviolet-light region. Finally, the thermodynamic properties of LiBeF3, including the bulk modulus B, relative volume, heat capacities, thermal expansion α and relative Debye temperature at various temperatures and pressures, are discussed. The optical and thermodynamic properties, and their relationships of cubic crystal LiBeF3 are reported for the first time. Our results indicate that LiBeF3 compound is a promising optoelectronic and optics applications.