Giant Rotational Magnetocaloric Effect in Ni(en)(H2O)4·2H2O: Experiment and Theory

An experimental study of the rotational magnetocaloric effect in Ni(en)(H2O)4SO4∙2H2O (en = ethylenediamine) single crystal is presented. The was carried out at temperatures above 2 K and associated with adiabatic rotation between easy plane hard axis magnetic fields up to 7 T. properties studied system were investigated by isothermal magnetization measurement. observations completed ab initio calculations anisotropy parameters. A large entropy change ≈12 Jkg−1K−1 ≈16.9 achieved 5 T T, respectively. present suggests a possible application this material low-temperature refrigeration since led cooldown sample from initial temperature 4.2 down 0.34 K. Finally, theoretical show that S 1 Ni(II)-based systems easy-plane can have better than costly materials containing rare-earth elements their chemical structures.