The pressure effects on electronic, thermoelectric, thermodynamic, and optical features of Li₃Bi

First-principles electronic, thermoelectric, thermodynamic, and optical calculations of an alkali pnictide compound, Li₃Bi, are implemented by WIEN2k, BoltzTraP and Gibbs2 using density functional theory in the presence of spin–orbit coupling. The generalized gradient approximation and modified Becke and Janson functionals with the generalized gradient approximation are utilized for the treatment of exchange and correlation potential. The Li₃Bi electronic band structure indicates that this compound is a semiconductor at zero pressure. The energy band gap of this compound closes at a pressure of 6.0 GPa. In contrast, low pressures enhance the energy band gap and reduce the band width of the valence and conduction bands. The pressure and temperature effects on the thermoelectric and thermodynamic performance of this compound are investigated. This results reveal (1) an increase in the power factor values under high temperatures and low pressures, (2) a reduction in the thermal expansion and the specific heat capacity at constant volume and an increase in the Debye temperature under high pressures at constant temperature. Also, the evaluation of optical properties under various hydrostatic pressures shows an increase in the static real part of the dielectric function and the static reflectivity of Li₃Bi at a pressure of 6 GPa.

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Recommended citation: Mitra Narimani, Shahram Yalameha, Zahra Nourbakhsh, Journal of Computational Electronics 20 (6), 2300-2307.