Electronic structure, magnetic and thermal properties of Rh sub(2)MnZ (Z=Ge, Sn, Pb) compounds under pressure from ab-initio quasi-harmonic method

We have investigated the electronic structure, magnetic and thermal properties of the ternary full-Heusler alloys Rh sub(2)MnZ (Z=Ge, Sn, Pb) under pressure employing the full potential linearized augmented plane wave (FP-LAPW) plus local orbitals method based on the density functional theory (DFT), For the exchange-correlation effects we have adopted the generalized gradient approximation (GGA).Through the quasi-harmonic Debye model, we also study the thermodynamic properties of Rh sub(2)MnZ (Z=Ge, Sn and Pb). The thermal expansion versus temperature and pressure, the thermodynamic parameters (Debye temperature and specific heat) with pressure P, and the heat capacity at various pressures and temperatures in the ranges of 0 GPa to 0.6 GPa and 0 K to 400 K have been obtained.