Synthesis, structures and luminescence properties of two mixed nickel(II) coordination polymers bearing a rigid bis-triazole linker

Two Ni(II) coordination polymers, namely [Ni3(btb)4(nbta)2(H2O)4] n (1) and [Ni(btb)(Hbtc)(H2O)2] n (2) (H3nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, H3btc = 1,2,4-benzenetricarboxylic acid), employing mixed-ligand systems, both containing the rigid N-donor ligand btb (4,4′-bis(1,2,4-triazolyl-1-yl)-biphenyl), have been synthesized and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Complex 1 shows a two-dimensional network with a binodal (3,4)-connected 3,4L90 topology, while complex 2 features a 1D zigzag chain structure. Both complexes are further extended into 3D supramolecular architectures via strong O–H···O hydrogen bonds. The thermal stabilities and luminescence properties of both complexes have been studied.