First-principles investigation of structural, mechanical, and electronic properties of AMgX₃ (A=Ga, In, Tl, and X=Cl, Br, I) perovskites for optoelectronic applications

Abstract Metal-halide perovskites have emerged as a revolutionary material in solar energy technology, offering exceptional light-harvesting efficiency, eco-friendly characteristics, and low production costs. These materials are paving the way for next-generation photovoltaic devices with their outstanding optoelectronic properties and scalability for commercial applications. To determine the various features of the halide perovskites AMgX 3 (where A stands for Ga, In, Tl, and X for Cl, Br, and I), we utilized DFT with the (Generalized Gradient Approximation) GGA-PBE (Perdew–Burke–Ernzerhof) exchange and correlation approximation to examine the structural, mechanical, electronic, and optical behaviors of the perovskite materials. Structurally, these materials exhibit cubic stability, vital for high-performance durability in photovoltaic devices. Mechanically, the calculated elastic constants verify their strength, suitable for environments where mechanical stability is critical, such as in aerospace electronics. The band gap range (1.22–3.69 eV) shows how versatile the materials are. TlMgI 3 is suitable for infrared (IR) detection, whereas GaMgCl 3 and InMgCl 3 are optimal for ultraviolet (UV) applications. These findings support applications from IR sensors to UV photo detectors. The compounds’ optical properties, such as their high absorption coefficients, dielectric constants, and reflectivity, show how well they can collect and send light, which is important for solar cells and LEDs. The mechanical and optoelectronic properties collectively enhance their suitability for photonic and thermoelectric devices, offering scalable solutions for renewable energy and advanced photonics applications.