Detail computational study about the structural, electronic, optical, and mechanical properties of RbVX (Cl, Br, I) halide perovskite materials.

The non-toxic nature of lead-free materials with cubic perovskite structure has attracted the researcher's attention, and huge work is ongoing for the search of such materials. Furthermore, due to demand for their utilization in diverse applications, such as photovoltaic and optoelectronics, these inorganic-halide materials have become more enchanting for engineers. In the present work, all the key properties, including structural, electronic, optical, and mechanical, of rubidium based RbVX (where X is chlorine, bromine, and iodine) materials were extensively studied first-principle density functional theory (DFT). The study reveals the half-metallic nature of the currently studied materials. For the mechanical stability of RbVX compounds, all three independent elastic coefficients () were determined, from which it was concluded that these materials are mechanically stable. Moreover, from the Poison and Pugh's ratios, it was found that the RbVCl and RbVBr materials have ductile nature, while RbVI has brittle nature upon the applied stress.