Magnetic properties and magnetocaloric effects in (Ho1−xYx)5Pd2 compounds**Project supported by the National Basic Research Program of China (Grant No. 2014CB643703), the National Key Research and Development Program of China (Grant No. 2016YFB0700901), the National Natural Science Foundation of China (Grant Nos. 51261004 and 51761007), and Guangxi Natural Science Foundation, China (Grant No. 2018GXNSFAA294051).

Abstract

The crystal structure, magnetic and magnetocaloric properties of (Ho1−xYx)5Pd2 (x = 0, 0.25, and 0.5) compounds are investigated. All the compounds crystallize in a cubic Dy5Pd2-type structure with the space group Fd3m and undergo a second order transition from spin glass (SG) state to paramagnetic (PM) state. The spin glass transition temperatures Tg decrease from 26 K for x = 0 to 13 K for x = 0.5. In the PM region, the reciprocal susceptibilities for all the compounds obey the Curie–Weiss law. The paramagnetic Curie temperatures () for Ho5Pd2, (Ho0.75Y0.25)5Pd2, and (Ho0.5Y0.5)5Pd2 are determined to be 32 K, 30 K, and 22 K, respectively, and the corresponding effective magnetic moments ( are 10.8 /Ho, 10.3 /RE, and 7.5 /RE, respectively. Magnetocaloric effect (MCE) is anticipated according to the Maxwell relation, based on the isothermal magnetization curves. For a magnetic field change of 0–5 T, the maximum values of the isothermal magnetic entropy change of the (Ho1−xYx)5Pd2 (x = 0, 0.25, and 0.5) compounds are determined to be , , and , with corresponding refrigerant capacity values of , , and , respectively.