Ab initio predictions of the structural, electronic, optical, elastic, and thermoelectric properties of quasi-two-dimensional BaFZnP

Abstract

We studied the structural parameters, elasticity, electronic structure, linear optical spectra, and thermoelectric coefficients of quasi-two-dimensional BaFZnP using ab initio methods. The computed equilibrium coordinates of atomic positions and lattice parameters were in good agreement with existing results. We derived numerical values for the elastic moduli and related physical parameters, such as the independent monocrystalline elastic constants, modulus of compressibility, modulus of shear, Poisson's ratio, Young's modulus, isotropic sound velocities, Debye temperature, ductility/brittleness nature, and elastic anisotropy. We examined the electronic properties including the energy band dispersions, density of states, and charge carrier effective masses, and concluded that BaFZnP is a semiconductor with a direct bandgap. The linear optical functions were explored in an energy window of 0–15 eV for incident electromagnetic waves polarized parallel to the [100] and [001] crystal directions. Numerical evaluation of the dependencies of the thermoelectric coefficients on charge carrier concentration and temperature shows that the thermoelectric characteristics of the p-doping BaFZnP are better than the corresponding ones of the n-doping BaFZnP over the charge carrier concentration range of 1016−1021cm−3. The p-doping BaFZnP with a hole concentration of around 1.81×1020 cm−3 possesses a figure of merit of 1.16 at 900 K, making it suitable for thermoelectric application.