MoO42--templated Ln(20)Ni(21) heterometallic clusters with large low-field magnetic entropy

The anionic template method is an effective strategy for synthesizing high-nuclearity transition-lanthanide (3d-4f) heterometallic clusters. Herein, two lanthanide clusters with formulas [Gd20Ni21(mu(3)-OH)(21)(CO3)(6)(IDA)(21)(C2H4NO2)(6)(C2O4)(3)(MoO4)(1.5)(mu(2)-OH)(1.5)(H2O)(9)]Cl-10.5 center dot 79H(2)O (1) and [Tb20Ni21(mu(3)-OH)(21)(CO3)(6)(IDA)(21)(C2H4NO2)(6)(C2O4)(3)(MoO4)(mu(2)-OH)(2)(H2O)(10)]Cl-11 center dot 32H(2)O (2) were synthesized by introducing MoO42- anions as templates. Structural analysis indicates that compounds 1 and 2 are isomorphic, featuring a fascinating triangular-shaped metal framework. Magnetic property investigations illuminate the fact that compound 1 exhibits a large -Delta Sm of 37.83 J kg(-1) K-1 at 3 K for Delta H = 7 T. In particular, it is worth mentioning that compound 1 has an excellent low-field magnetic entropy (-Delta S-m = 23.85 J kg(-1) K-1 at 2 K, 2 T).