First-principles calculation of structural, electronic, optical and thermoelectric properties of Li3TrAs2 (Tr = Al, Ga)

Abstract

Computational analysis of the materials Li₃TrAs₂ (Tr = Al, Ga) through first principles DFT approach using WIEN2k code was done to evaluate the feasibility of the materials for several applications. The study comprises structural, electronic, optical and thermoelectric parameters. Structural parameters for the orthorhombic compounds with c/a variation in accordance to ground state energy is in well agreement with experimental data. From the electronic properties, direct bandgap semiconducting behavior of both compounds has been observed. Optical studies such as absorption coefficient and its direct bandgap nature implying the materials capability in utilizing in optoelectronic devices. Higher figure of merit (ZT) at ambient conditions implies the material to be good contender in thermoelectric devices such as waste heat recovery systems at room temperature. Based on the exciton binding energy from excitonic study reveals the weak or Mott-Wannier type exciton within both the material.