Heterodinuclear [(NiIIL)LnIII(hfac) 2(EtOH)] (H3L = 1,1,1-tris[(salicylideneamino)methyl] ethane; Ln = Eu, Gd, Tb, and Dy; hfac = hexafluoroacetylacetonate) complexes (1·Ln) were prepared by treating [Ni(H1.5L)]Cl0.5 (1) with [Ln(hfac)3(H2O)2] and triethylamine in ethanol (1:1:1). All 1·Ln complexes (1·Eu, 1·Gd, 1·Tb, and 1·Dy) crystallized in the triclinic space group P1 (No. 2) with Z = 2 with very similar structures. Each complex is a face-sharing dinuclear molecule. The NiII ion is coordinated by the L3- ligand in a N3O3 coordination sphere, and the three phenolate oxygen atoms coordinate to an LnIII ion as bridging atoms. The LnIII ion is eight-coordinate, with four oxygen atoms of two hfac-,s, three phenolate oxygen atoms of L3-, and one ethanol oxygen atom coordinated. Temperature-dependent magnetic susceptibility and field-dependent magnetization measurements showed a ferromagnetic interaction between NiII and GdIII in 1·Gd. The NiII-LnIII magnetic interactions in 1·Eu, 1·Tb, and 1·Dy were evaluated by comparing their magnetic susceptibilities with those of the isostructural ZnII-Ln III complexes, [(ZnL)Ln(hfac)2(EtOH)] (2·Ln) containing a diamagnetic ZnII ion. A ferromagnetic interaction was indicated in 1·Tb and 1·Dy, while the interaction between Ni II and EuIII was negligible in 1·Eu. The magnetic behaviors of 1·Dy and 2·Dy were analyzed theoretically to give insight into the sublevel structures of the DyIII ion and its coupling with NiII. Frequency dependence in the ac susceptibility signals was observed in 1·Dy.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry