Transition metal coordination complexes based on V-shaped bis-triazole ligand: syntheses, structures, and properties

Abstract

Hydrothermal reactions of 1,3-bis(1,2,4-triazol-1-yl)benzene (btb) and M(NO3)2 (M = Co2+ (1), Cu2+ (2)) afforded two new coordination polymers, [Co(btb)2(NO3)(H2O)]n·NO3·H2O (1) and [Cu(btb)2(NO3)2]n (2), respectively. Single-crystal X-ray diffraction reveals that 1 crystallizes in the space group P21/m and 2 crystallizes in the space group Pī, both showing a double-stranded chain structure. The 1-D chains are interconnected via π⋯π interactions to lead to 2-D ladder-like supramolecular architectures. In addition, magnetic behavior and thermal stability of 1 and 2 have been investigated. For 1, weak antiferromagnetic interactions are observed at low temperature, and the data obey the Curie–Weiss law χM = C/(T−θ), with C = 3.22 cm3·mol−1·K and θ = −10.39 K. For 2, the decrease of the χT vs. T curve at low temperature is the result of intermolecular antiferromagnetic magnetic interactions.