Ab-initio investigation of structural, electronic, magnetic, and thermodynamic properties of XPt3 (X=V, Cr, Mn, and Fe) intermetallic compounds

We present first-principles calculations of the structural, electronic and magnetic properties of XPt3 (X = V, Cr, Mn and Fe) compounds in the L12 structure. The computational method is based on the full-potential linearized augmented plane wave method (FP-LAPW). The exchange and correlation energy is described in the local density approximation (LDA) and generalized gradient approximation (GGA). The results obtained are in a good agreement with experimental and theoretical values concerning the lattice constant and the total and local magnetic moments. The LDA is found to underestimate the equilibrium lattice constant and give a larger total energy compared to the GGA calculations. Using the quasi-harmonic Debye model, the effect of pressure P and temperature T on the bulk modulus B0, lattice volumeV0, thermal expansion coefficient α, Debye temperature ӨD, heat capacity Cv and entropy S for these compounds are investigated for the first time.