Two New Isomorphous Zinc(II) and Nickel(II) Supramolecular Coordination Polymers Based on the (benzotriazol-1-yloxy)-Acetic Acid Ligand: Syntheses, Structures, Properties, and DFT Analyses

Two new isomorphous zinc(II) and nickel(II) supramolecular complexes, [Zn(L)(2)(H2O)(2)](n), (1), and [Ni(L)(2)(H2O)(2)](n) (2) {HL=(benzotriazol-1-yloxy)-acetic acid} have been synthesized under ambient conditions by the self-assembly of HL with Zn(Ac)(2)2H(2)O or Ni(Ac)(2)4H(2)O in the presence of triethylamine. The two complexes have been characterized by single-crystal X-ray diffraction, elemental analysis, and IR spectroscopy. Single-crystal X-ray diffraction shows that the two complexes are isostructural and crystallize in monoclinic crystal system P2(1)/c with similar unit-cell parameters and exhibit one-dimensional infinite chain structures. Adjacent chains are linked by O-HO hydrogen bonds, giving rise to a two-dimensional network and these networks are further extended by weak stacking interactions among adjacent aromatic cycles of HL ligands into a three-dimensional framework. In addition, the luminescent property of 1 and UV-Visible absorbance of 2 were also investigated and discussed. Density functional theory (DFT) calculations of the structures, stabilities, orbital energies, and composition characteristics of some frontier molecular orbitals of the two complexes were performed by means of Gaussian 09W package and taking B3LYP basis set.