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A family of new TbIII and 3d–TbIII cluster complexes, namely [Tb(L)(CH3COCH3)] (1), [Tb2(μ-H2O)(L)2] (2), [Zn2Tb(L)2]·ClO4 (3) and [Ni2Tb(L)2]·ClO4 (4) (H3L = N,N′,N′′-tris(3,5-dimethyl-2-hydroxybenzyl)-1,4,7-triazacyclononane), have been synthesized through the reaction of H3L and metal salts. Structural analysis reveals that 1 and 2 exhibit mononuclear and binuclear structures, respectively, and both 3 and 4 exhibit trinuclear 3d–4f–3d structures. Interestingly, complex 1 could undergo reversible transformation to complex 2 by adjusting the reaction solvents. The alternating current (ac) magnetic susceptibilities of 3 reveal that out-of-phase (χ′′) is frequency- and temperature-dependent, which is a typical feature of field-induced slow magnetic relaxation with an energy barrier of 35.71 K. Moreover, complexes 1–3 show strong oxygen-sensitive luminescence, with typical narrow emission bands of lanthanide ions. The luminescence intensity and lifetime (5D4 of TbIII) of 3 are obviously stronger than those of 1 and 2. Therefore, complex 3 can be considered as a good candidate as a bi-functional magneto-luminescent molecular material. [ABSTRACT FROM AUTHOR]

Two bulky ion-pair crystals [N(C3H7)4]2[Ln(NO3)5] (Ln = Tb or Dy) are synthesized and structurally characterized. Both compounds exhibit a dielectric bistable behaviour accompanied by a reversible structural phase transition above room temperature. In addition, the relatively rigid coordination configuration around the lanthanide ions makes the two ion-pair compounds function as promising green and yellow phosphors, respectively. The synthetic approach may be applicable to construct other multifunctional materials with dielectric bistability and luminescence based on large organic ammonium and lanthanide complex anions. [ABSTRACT FROM AUTHOR]