Magnetic and thermodynamic study of the interplay between magnetism and structure in CrOCl

Magnetic materials associated with the structural phase transition has brought considerable interest. CrOCl is found to provide a fertile setting for studying the interplay between magnetism and atomic structure. In particular, its magnetic ordering transition has been observed accompanying by an orthorhombic-to-monoclinic structural transition, yet the detailed thermodynamic properties of this transition remain to be further investigated. Here, by systematically measuring the low temperature magnetic properties of CrOCl, we observe thermal hysteresis behaviors in both temperature and magnetic field scans, demonstrate the first-order nature of such a complex phase transition. The entropy change during the phase transition is also estimated by two different methods, providing further quantitative characterizations of it. Our results thus not only give detailed insights on the phase transition involving both magnetism and structure, but also imply its potential for applications in, for example, magnetic refrigeration.