Magnetic properties and magnetic entropy change in spinels (Cd,M) Cr ₂ S₄ with M=Cu or Fe

Magnetic properties and magnetic entropy changes in spinels (Cd,M) Cr2 S4 with M=Cu or Fe have been studied. The saturation moments per formula unit are about 4.77 μB for Cd0.8 Cu0.2 Cr2 S4 and 4.41 μB for Cd0.7 Fe0.3 Cr2 S4. Magnetic transition in Cu- and Fe-doped samples are of second order in nature, and their Curie temperatures are TC =86 and 119 K, respectively. The maximum values of magnetic entropy change ΔS are found to be 5.1 and 5.4 Jkg K for Cd0.8 Cu0.2 Cr2 S4 and Cd0.7 Fe0.3 Cr2 S4 for a field change from 0 to 5 T, respectively. The significant ΔS suggests a potential of the sulfospinel as a magnetic refrigerant in the corresponding temperature range.