First principles study of structural, electronic, optical and thermodynamics properties of Rb2AgAsA6 (A = Br and I) compound for optoelectronic devices

Abstract

Perovskite substances are thought to be the starting point for a wide range of physical applications in the sectors of electronic and energy manufacturing applications. The first principle calculations (CASTEP) are used with GGA-PBE functional to analyze the physical characteristics of halide perovskite Rb₂AgAsA₆ (A = Br and I) substances. The substances have 40 atoms per unit cell in the cubic form and belong to the space group 221 (Pm3 m). According to results, the Rb₂AgAsA₆ compound's stability is confirmed via tolerance factor (0.84 and 0.86) and formation energy (−836.176 and −985.566), accordingly. The elastic parameters (C_ij) are used to influence the flexibility (v = 0.26 and 0.28, B/G = 1.77 and 1.96), the anisotropic features (A = 0.17 and 0.24), and the Born mechanical stability of Rb₂AgAsA₆ materials (A = Br and I). They also determined the light absorption and conductivity in the visible/UV range and its transparency to low-energy photons and refractive index in the energy limits from 0.0 to 30.0 eV. Our calculated results suggest that Rb₂AgAsA₆(A = Br and I) materials are well-suited for energy claims and show great potential for advanced devices, such as optoelectronic devices.