Investigating the physical properties of Li2AgGaX6 (X = Cl, Br, I) double perovskites using ab initio calculations

Abstract

The double perovskites have emerged as focal point of exploration and innovation in energy harvesting applications. In this paper, we elucidate the mechanical, optical, and transport properties of Li2AgGaX6 (X = Cl, Br, I) through the application of DFT-based simulations by employing the WIEN2K software. The calculation of formation energy has been conducted to assess thermodynamic stability. The band structures of studied halides doped double perovskites have reported values of direct band gaps. These findings have implications for a variety of optoelectronic and transport applications due to their diverse characteristics. The peaks of the absorption band are shifted toward the lower frequency spectrum, and their width increases as we shift from Cl to I. Furthermore, thermoelectric attributes such as the Seebeck coefficient (S), power factor (σS2), and figure of merit (ZT) have been evaluated across the thermal spectrum range (200–600) K Low value of thermal conductivity and substantial ZT at standard temperature (300 K) indicate their profound significance in thermoelectric developments.