Synthesis and Characterization of Two Distinct 2D Nickel(II) Coordination Polymers From Dicarboxylate and Flexible Bis(imidazole) Ligands

Two nickel(II) coordination polymers, formulated as {[Ni-2(bix)(2)(tbta)(2)(H2O)(4)]0.25H(2)O}(n) (1) and [Ni-2(bix)(aip)(2)(H2O)(2)](n) (2) [bix = 1, 4-bis(imidazol-1-ylmethyl)benzene, H(2)tbta = tetrabromoterephthalic acid, H(2)aip = 5-aminoisophthalic acid] were synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction methods, IR spectroscopy, TGA, and elemental analysis. Complex 1 exhibits a 2D (4, 4) layer with {4(4).6(2)} topology. Complex 2 shows 2D (3, 4)-connected 3,4L83 sheets, which are finally extended into an unusual (5, 6)-connected 3D supramolecular network by classic hydrogen bond interactions. Fluorescence, UV/Vis diffuse reflection spectra, and catalytic properties of two complexes for the degradation of the methyl orange dye in a photo-Fenton-like process were investigated.