Hydrogen induced antiferromagnetism in CeNiSn studied by heat capacity and magnetocaloric effect

Hydrogenation of CeNiSn provokes a change of the ground state of cerium from Kondo insulator to antiferromagnetic (CeNiSnH1.0) or ferromagnetic (CeNiSnH1.8) behaviour. We report heat capacity measurements in CeNiSnH1.0 performed in magnetic fields up to 90kOe. The calculated magnetocaloric effect has a maximum at temperatures close to TN=4.5K. The values of the isothermal magnetic entropy (ΔSm) and the adiabatic temperature change (ΔTad) are modest, and similar to those found in other Ce compounds. The field dependence of both, heat capacity and magnetocaloric effect clearly indicate the nature of the magnetic transition