A [Cu3] Cluster-Based Chain Featuring Linkages of Acylhydrazone N–N Single Bonds and Cl− Ions: Synthesis, Structure and Magnetic Properties

Abstract

A Cu coordiantion polymer, namely, [Cu3(ovph)(Py)2Cl2] (1) [H4ovph = N,N′-bis(o-vanillidene)pyridine-2,6-dicarbohydrazide]; Py = Pyridine], was synthesized by solvothermal reaction of copper acetate and diacylhydrazone ligand H4ovhp. It was characterized by element analysis, FT-IR, thermogravimetric analysis, PXRD and single crystal X-ray diffraction. Structural analysis indicated that the N–N bonds of its ovph4− ligands bridge the Cu2+ ions to form quasi-linear [Cu3] cluster-based units, which were further linked together by in situ generated µ-Cl−, giving rise to a rare Cu chain structure containing two kinds of magnetic exchange pathways. Variable temperature magnetic measurements revealed that both N–N and Cl− bridges convey antiferromagnetic couplings, with the best fitting JN–N = − 99.95 cm−1, JCl = − 5.70 cm−1, zj = − 1.17 cm−1 and g = 2.00.