Structural, electronic and thermoelectric properties of the intermetallic materials based on Mg2X (X= Si, Ge, Sn): DFT calculations

Abstract

The scope of this work is the investigation of the physical properties of chalcopyrite materials using ab-initio methods in order to  simulate a new structure of thin-films photovoltaic cells with high conversion efficiency. In the first framework, we obtained the results of calculations based on Density Functional Theory (DFT) using the full-potential linearized augmented plane wave method (FP-LAPW) as  involved in the WIEN2K computational package. For the exchange-correlation potential, the local density approximation (LDA) was used  to calculate the lattice parameters, Bulk modulus and its first derivative as well as the densities of states of the intermetallic  semiconductors materials based on Mg2X (X=Si, Ge and Sn). The semilocal Becke-Johnson (mBJ) potential and its modified form proposed  by Tran and Blaha (TB-mBJ) were also used for studying the electronic and thermoelectric properties; (merit factor, Seebeck coefficient, electronic conductivity). The achieved results were compared to computational works and other data acquired experimentally.