Abstract
Magnesium-based perovskites are being investigated for their electronic, mechanical, and thermoelectric properties using density functional theory and Boltzmann transport theory. The structural, thermodynamic, and mechanical stabilities of MgSiO3, MgGeO3 and MgSnO3 are confirmed by tolerance factor (0.93-1.0 the stability range for cubic structure), enthalpy of formation, and Born mechanical stability criteria, respectively. The ductile nature of studied materials has been explored by Pugh's (B/G > 1.75) and Poisson (upsilon > 0.26) ratios. The studied compounds are indirect bandgap semiconductors having band gap range 2.5 eV to 0.7 eV and, correspondingly, their thermoelectric properties are modified. The small values of sigma/kappa ratio and large values ZT (0.57, 0.66, and 0.67) at room temperature make them suitable for thermoelectric applications.