Pressure Effect On The Structural, Electronic, And Thermal Properties Of Chalcopyrite Compounds Mgsias2 And Besias2

The structural, electronic, and thermal properties of the BeSiAs2 and MgSiAs2 chalcopyrite compounds have been investigated using the full-potential linearized augmented plane wave (FP-LAPW) method. The exchange-correlation part of the potential is treated within the Wu and Cohen generalized gradient approximation (WC-GGA). Moreover, Tran and Blaha modified Becke-Johnson (TB-mBJ) scheme is also applied for electronic properties. Our calculated ground-state properties, including the lattice constants, internal parameters, and the bulk moduli are found in reasonable agreement with the available data. The computed band structures reveal a direct bandgap semiconducting nature of both compounds. The thermodynamic properties are also predicted through the quasi-harmonic Debye model. We also analyze the effect of pressure on the structural phase transition and the electronic properties, besides investigating the effect of temperature and pressure on the bulk modulus, heat capacities, and the Debye temperatures of the title materials. (C) 2020 Elsevier B.V. All rights reserved.