Physical properties of Be-Based fluoroperovskite compounds XBeF(X = K, Rb): a first-principles study.

In this work, we have conducted an ab initio computational research of the pressure impact on the structural, elastic, thermodynamic, electronic, and optical properties of Be-based fluoroperovskite XBeF3 (X= K, Rb) compounds by using GGA+ PBEsol functional based on DFT in the CASTEP Package. These compounds' ground state characteristics were examined, including the lattice parameters, coefficient compressibility (B), and its pressure derivative(B'). Structural characterization shows that these compounds keep a cubic crystal structure with the impact of stress till 18 GPa.