Probing the structural, opto-electronic, mechanical, and thermoelectric properties of novel lead free semiconductor double perovskites Rb₂MgMnX₆ (X = Cl, Br, I): First principle study

Halide Double perovskites are promising materials for generating green energy that could fulfill worldwide desires for addressing energy scarcity crises. The structural stabilities of the scrutinized materials have been ascertained from the simulated formation energy and Goldsmith tolerance factor. On the other hand, the demonstrated Pugh's ratio depicts the ductile nature of the studied materials. The electronic band structure and density of states are determined using Generalised gradient approximation and modified Becke-Johnson potential. The calculated magnetic moment is 5 mu B, mainly due to the contribution of the d -Mn atom. Our obtained values show a significant light absorption in the visible range, which illustrates the materials' potential for use in optoelectronic devices. The thermoelectric properties have also been investigated regarding Seebeck coefficient, electrical conductivity, thermal conductivity, and figure of merit zT.