A New One-dimensional Complex Assembled by 4-Nitrobenzoic Acid and Bis(imidazol) Ligands: Syntheses, Structures and Theoretical Calculations

A new Zn(II) coordination polymer, [Zn(nba)(2)(mbix)](2n) (1, Hnba = 4-nitrobenzoic acid, mbix = 1,3-bis(imidazol-1-ylmethyl)-benzene), was synthesized and characterized by elemental analyses, IR spectra, TG, fluorescence spectroscopy, single-crystal and powder X-ray diffractions. It belongs to the triclinic system, P (1) over bar space group, with a = 9.341(2), b = 13.029(3), c = 23.660(6) angstrom, alpha = 99.603(6)degrees, beta = 90.461(6)degrees, gamma = 90.597(5)degrees, V = 2838.9(12) angstrom(3) and Z = 2. It shows one-dimensional chains which are further linked by C-H center dot center dot center dot O hydrogen bonds and pi-pi stacking interactions to yield a three-dimensional supramolecular structure. In addition, the Natural Bond Orbital (NBO) was analyzed in using the PBEO/LANL2DZ method built in Gaussian 09 Program. The calculation results indicated obvious covalent interaction between the coordinated atoms and Zn(II) ion.