Efficiently increasing low-field magnetic entropy by incorporating SO 3 2- into Gd22Ni21 clusters.

The distinct nanosized cluster Gd 22 Ni 21 was isolated using a mixture of anions (SO 3 2- and SO 4 2- ) as templates, and to the best of our knowledge, this was the first such 3d-4f cluster to have been developed. Additionally, of a number of 3d-4f heterometallic clusters, Gd 22 Ni 21 showed the largest low-field magnetic entropy change (26.1 J kg -1 K -1 ) at 2.0 K and Δ H = 2.0 T.