Theoretical pursuit of structural, mechanical, magneto-electronic, and thermoelectric features of new inverse full Heusler compounds Rb₂ZrZ (Z = C, Si, Ge, and Sn). A first-principles investigation

In this study, based on the augmented plane wave method (FP-LAPW) as implemented in the Wien2k code, we investigated the structural, mechanical, magnetoelectronic, and thermoelectric properties of Full-Heusler Rb₂ZrZ (Z = C, Si, Ge, Sn) compounds. The results of optimization showed that all Rb₂ZrZ alloys are stable in the Hg₂CuTi-type structure. The calculation of elastic constants and other mechanical parameters was performed, which has shown that all compounds are stable and have a ductile nature. The analysis of the electronic structure using the GGA approximation and improved it by Tran Blaha modified Beck-Johnson confirm that the studied compounds have a half-metallic behavior with a total magnetic moment of . Using the semi-classical Boltzmann transport theory within the constant relaxation time approximation and Slack's equation, we obtained the thermoelectric properties and lattice thermal conductivity, respectively. Rb₂ZrZ compounds have moderate thermal conductivity, a great power factor, and a high Seebeck coefficient at room temperature. The maximum values of the figure of merit were found at 900 K to be 0.52, 0.62, 0.67, and 0.59 for Rb₂ZrC, Rb₂ZrSi, Rb₂ZrGe, and Rb₂ZrSn, respectively, which predicts the possibility of using these materials in thermoelectric applications in the future. (author)