Computational Modelling of the structural, phase stability, electronic, optical, and elastic behaviour of layered perovskites Rb2AgAsM6 (M = Cl and F) halide materials for optoelectronics Devices

The computational modeling of Rb₂AgAsM₆ (M = Cl and F) double perovskite halides is thoroughly examined in this work using the DFT model. Rb₂AgAsM₆ compounds ensured their prospective utility by meeting stability requirements for cubic structures. Formation (−817.951, −925.63) eV/atoms, cohesive (817.951, 925.63) eV/atoms energy, and tolerance factor (0.89, 0.78) of the compounds Rb₂AgAsM₆ (M = Cl and F) are measured for structural and thermal stability. Using the GGA-PBE approx., We found that the indirect electronic band gaps of Rb₂AgAsM₆ (M = Cl and F) fall between 1.34 eV and 2.29 eV. These values show that because of the strong spin-orbit coupling from heavy cations, the indirect band gaps of compounds fall inside the visible region. The Rb₂AgAsM₆ (M = Cl and F) compounds have mechanical Born stability, according to the calculated bulk modulus (41.254, 19.851) GPa. We found that when photon energy (eV) is applied to the Rb₂AgAsM₆ (M = Cl and F) compounds, the complex dielectric function promotes the greatest electron transition and absorption efficiency. These results highlight the potential of double perovskites made of Rb₂AgAsM₆ compounds for energy applications. According to DFT analysis, our study demonstrates the stability and advantageous characteristics of Rb₂AgAsM₆ (M = Cl and F) double perovskites. These findings underscore the potential of Rb₂AgAsM₆ (M = Cl and F) perovskites as environmentally friendly materials for advanced solar cells, optoelectronic devices, and next-generation technologies.