Theoretical investigation of structural, electronic, elastic, magnetic, thermodynamic, and thermoelectric properties of Ru2MnNb Heusler alloy: FP-LMTO method

This study investigates the structural stability, electronic, elastic, magnetic, thermodynamic, and thermoelectric properties of Ru2MnNb alloy by employing first-principles calculations based on the density functional theory (DFT). Using the generalized gradient approximation (GGA), it is found that the Ru2MnNb alloy is stable in the ferromagnetic (FM) state of Cu2MnAl type structure. The electronic results indicate that Ru2MnNb is a metal and has a conductive character; its magnetic moment is found to be 4.13 (mu B). It is also found to be elastically stable and ductile. The thermodynamic properties of Ru2MnNb, such as volume variation (V), compressibility modulus (B), Debye temperature, thermal expansion, specific capacity (Cp), and thermal capacity (Cv), are obtained by quasi-harmonic Debye model. At the end, the dependence of Seebeck coefficient (S), power factor, and figure of merit (ZT) on the Fermi level are investigated.