Synthesis, Crystal Structure and Theoretical Calculations of a Cadmium(II) Coordination Polymer Assembled by 5-Nitroisophthalic Acid and 1,3-Bis(imidazol-1-ylmethyl)-benzene Ligands

A new Cd(II) coordination polymer based on 5-Nitroisophthalic acid (H2NIPH) and 1,3-bis(imidazol-1-ylmethyl)benzene (mbix), namely, [Cd(NIPH)(mbix)](n) (1), has been successfully synthesized under hydrothermal conditions. Its structure has been determined by single crystal X-ray diffraction analysis, elemental analyses, IR spectroscopy, TG and fluorescence spectrum. Compound 1 shows a two-dimensional network structure. The intermolecular C-H center dot center dot center dot O hydrogen bonding and pi-pi stacking interactions extend the compound 1 into 3D supramolecular architectures and play an important role in stabilizing compound 1. In addition, natural bond orbital analysis was performed by using the PBE0/LANL2DZ method built in Gaussian 03 Program. The calculation results showed the obvious covalent interaction between the coordinated atoms and Cd(II) ion.