Synthesis, crystal structure and magnetic properties of cubane and linear trinuclear nickel complexes formed by 3,5-dichloro-2-hydroxybenzylaminoacetic acid

The reaction of Ni(ClO4)2·6H2O with 3,5-dichloro-2-hydroxy-benzylaminoacetic acid (H2dchaa), NaN3 and triethylamine in methanol solution or water solution under solvothermal methods leads to the formation of two completely different NiII compounds: [HN(C2H5)3]8·[Ni4(dchaa)4(N3)4]2 (1) and [HN(C2H5)3]2·[Ni3(dchaa)4(H2O)4]2·(H2O)2 (2). The complexes 1 and 2 have been characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. Structure analyses reveal that complex 1 is a cubane cluster, while the complex 2 is a linear trinuclear cluster. The magnetic investigation shows that complexes 1 and 2 exhibit a ferromagnetic coupling between NiII ions. Ac susceptibilities of 1 and 2 reveal no frequency-dependent out-of-phase signals and the corresponding magnetic properties were discussed.