Elucidating the Structural, Electronic, Magnetic, Mechanical, Thermoelectric, and Thermodynamic Properties of TbCo₄ X ₁₂ (X = P, Sb) for Advanced Applications

In this piece of investigation, TbCo₄ X ₁₂ (X = P, Sb) Terbium -filled, Skutterudites have been precisely reported through DFT ab-initio calculations in the Trans Bhala modified Becke-Johnson (TB-mBJ) potential to extract the electronic, mechanical, along with thermal, and transport properties. Structural stability was confirmed through ground state energy calculations using the Birch-Murnaghan equation of state. Electronic structure analysis, combining Perdew-Burke-Ernzerhof Generalized Gradient Approximation (PBE-GGA) and Trans Bhala modified Becke Johnson (TB-mBJ) functionals, revealed a metallic nature with PBE-GGA and a half-metallic character with TB-mBJ. Specifically, energy gaps of 0.24 eV and 0.64 eV were determined for TbCo₄P₁₂ and TbCo₄Sb₁₂, respectively. Mechanical property calculations indicated a brittle nature for both compounds. Charge density analysis confirmed ionic bonding characteristics, suggesting chemical stability. High Seebeck coefficient (S) values and associated figure of merit (zT) suggest promising thermoelectric performance across a broad temperature range.