Terbium Triangle Bridged by a Triazole Nitronyl Nitroxide Radical with Single-Molecule-Magnet Behavior

An unprecedented cyclic Tb III -radical cluster, [Tb 3 (hfac) 6 (4-Me-3-NITtrz) 2 (OH) 3 ] ( 1 ), has been self-assembled from Tb(hfac) 3 ·2H 2 O and 4-Me-3-NITtrz in the presence of Cu(hfac) 2 ·2H 2 O. Alternating-current magnetic studies show that the Tb 3 cluster displays a dual slow relaxation of magnetization behavior under a zero direct-current (dc) field and a single relaxation process under an induced dc field with an effective energy barrier of 14 K, representing the first triangle 2p–4f cluster with a slow magnetic relaxation property.