Thermomagnetic properties and magnetocaloric effect of TmFe2 compound

We report on a theoretical study of thermomagnetic and magnetocaloric properties of TmFe2. The magnetization, total heat capacity, total entropy and magnetocaloric effect, namely isothermal entropy change ΔSm and adiabatic temperature change ΔTad, are calculated for magnetic fields up to 8 T and for temperatures up to 700 K. Mean- field analysis, within the two sublattice model, showed that TmFe2 is a ferrimagnetic compound exhibiting a compensation point at Tcomp = 200 K and a Curie temperature at TC = 550 K. Direct and inverse MCEs are shown to take place in this ferrimagnetic compound. We have calculated direct MCE with maximum |ΔSm| of 0.50 J/ mole K at Tc, and an inverse MCE with maximum |ΔSm| of 0.57 J/mole. K, for an applied field change of 8 T. |ΔTad| has its maximum value of 5.57 K in an applied field change of 8 T. i.e. a temperature drop of 0.70 K/T has been achieved. The calculated Arrott plots and the relation between |ΔSm| and M2 demonstrated that the magnetic phase transition in this compound is of the second order. The mean-field model proves its suitability for calculating the properties of the compound under study.