First-principles study of magnetic, electronic, elastic and thermal properties of GdFe2

The magnetic, electronic, elastic and thermal properties of GdFe2 have been investigated under ambient and hydrostatic pressure, in the pressure range 0-100 GPa using the Full Potential Nonorthogonal Local-Orbital minimum basis method (FPLO) within the generalized gradient approximation (GGA) and the local spin density approximation (LSDA). We have calculated the lattice constant, bulk modulus and its first pressure derivative. The bulk modulus using GGA is 104.05 GPa in fair agreement with experimental results. The total magnetic moment of GdFe2 using GGA and LSDA are 3.65 and 4.38 μB at ambient pressure respectively. The pressure effect on the partial, total magnetic moment and total DOS is investigated under high pressure the results indicate that GdFe2 is metallic under all applied pressure. The magnetic and thermal heat capacity and entropy for GdFe2 have been studied using results from ab-initio calculations and proper models. The magnetic heat capacity contributes only 0.5 J/g K at 793 K and the thermal heat capacity is saturated at 140 J/mol K above Debye temperature. The maximum contribution of the magnetic entropy to the total entropy is 0.8 J/g K in the studied temperature range.