Magnetic, magnetocaloric and transport properties in AlCMn3 antiperovskite compound

Highlights: • Structural, electronic, magnetic, magnetocaloric and transport properties of the antiperovskite compound AlCMn₃ are studied. • We have used ab initio calculations, Monte Carlo simulations and mean field theory for study this compound. • The crystal field and the parameters of the exchange coupling interactions have been investigated using ab initio methods. • The Curie temperature obtained by MCs is in good agreement with experimental value. • The AlCMn₃ antiperovskite may be considered as a potentially viable material for magnetic refrigeration at near-room temperature. In this work, the aim was to conduct a numerical study of the structural, electronic, magnetic, magnetocaloric, and transport-related properties of the antiperovskite compound AlCMn₃, by using several theoretical methods such as: ab initio calculations, Monte Carlo simulations, and mean field theory. This material exhibits a second-order ferromagnetic-paramagnetic phase transition around T_C = 287 K. The crystal field and the parameters of the exchange coupling interactions have been investigated using ab initio methods. A previous theoretical study based on the magnetoelastic and magnetoelectronic couplings was investigated in order to calculate the magnetocaloric effect (MCE) of AlCMn₃, but the results that were obtained using this method (namely a magnetic entropy change of -ΔS_m = 35 J/Kg. K) did not match the experimental value of -ΔS_m = 3.28 J/Kg.K under the same applied magnetic field of 4.5T, which is why we resorted to using the Monte Carlo simulation. This new approach improved MCE-related results as they ended up matching the experimental data, contrary to the magnetoelastic and magnetoelectronic couplings method. This suggests that AlCMn₃ may be considered as a potentially viable material for magnetic refrigeration at near-room temperature due to: (i) the large full width at half peak of its −ΔS_m (T) curve, (ii) the absence of any hysteresis loss, (iii) its near-room temperature working conditions and (iv) the low cost and innocuous nature of its raw materials.