Thorough study of the properties of the half-Heusler compounds TbPdBi and ErPdBi employing the ab initio method with GGA and GGA+U formalisms.

CONTEXT: Rare earth-containing half-Heusler compounds have attracted increasing attention because of their remarkable electronic, magnetic, optical, and thermoelectric properties, making them promising candidates for spintronic, optoelectronic, magnetoelectric, and energy-conversion applications. In this study, the structural, electronic, magnetic, optical, and thermoelectric properties of the half-Heusler compounds TbPdBi and ErPdBi were systematically investigated. The calculated formation energies confirm the energetic stability of both compounds in the ferromagnetic phase. Electronic structure calculations suggest a semimetallic character, with the magnetic moments mainly originating from the localized 4f states of Tb and Er atoms. Furthermore, the calculated optical and thermoelectric properties suggest that both compounds are promising candidates for advanced multifunctional devices. METHODS: First-principles calculations were performed using the full-potential linearized augmented plane wave (FP-LAPW) method implemented in the WIEN2k package within the framework of density functional theory (DFT). Exchange-correlation effects were treated using the generalized gradient approximation (GGA) and the GGA+U approach to account for strong on-site Coulomb interactions in the rare-earth 4f electrons (U = 6 eV). Thermoelectric transport coefficients were evaluated using semiclassical Boltzmann transport theory as implemented in the BoltzTraP code.