Synthesis and structural characterization of isothiocyanato-4-methoxypyridine-cobalt(II) complexes with diverse geometries and a bridged 1D coordination polymer showing metamagnetic transition

Three cobalt(II) isothiocyanato complexes with 4-methoxypyridine (4-MOP) as a co-ligand have been synthesized: catena-[Co(4-MOP)(2)(mu(1,3)-NCS)(2)] (1), trans-[Co(4-MOP)(4)(NCS)(2)] (2), and [Co(4-MOP)(2)(NCS)(2)] (3) and structurally characterized by IR, UV-Vis spectroscopy and single crystal X-ray diffraction. The complexes 2 and 3 are discrete monomeric species with octahedral and tetrahedral geometries, respectively whereas the catena-[Co(4-MOP)(2)(mu(1,3)-NCS)(2)] (1) is featuring a polymeric 1D system with doubly bridging NCS- groups through the terminals N- and S-donor atoms in a trans octahedral geometry. The thermoanalytical behavior of 1-3 is reported. Magnetic susceptibility of the bridged-isothiocyanato coordination polymer 1 was studied down to a temperature of 2 K and at various magnetic dc and ac fields. These measurements indicate a metamagnetic transition in 1. (C) 2018 Elsevier Ltd. All rights reserved.