A unique mixed-bridged trinuclear Co (II) complex and its extended system: Structural and magnetic studies

Two novel complexes, [Co3(N3)2(bca)4(phen)2] (1, bca = benzenecarboxylic acid, phen = 1,10-Phenanthroline) and [Co3(N3)2(bdc)2(phen)2]n (2, bdc = terephthalic acid), have been synthesized hydrothermally and characterized by single crystal X-ray diffraction (XRD), infrared spectra (IR) and element analysis (EA). Complex 1 features unprecedented discrete linear Co3 clusters that formed by mixed (μ-EO-N3)(μ-COO)2 (EO = end-on) triple bridges whereas 2 presents an extended (2D) network based on the similar trinuclear units as 1. Magnetic studies of 1 and 2 reveal that the mixed (μ-EO-N3)(μ-COO)2 triple bridges transmit ferromagnetic behavior.