From a 1-D chain, 2-D layered network to a 3-D supramolecular framework constructed from a metal-organic coordination compound

Three new metal-organic coordination polymers, Cd(bpdc)(phen)(2).2H(2)O (1) (H(2)bpdc = biphenyl-4,4'-dicarboxylic acid), Cd(BDC)(phen).DMF (2) (H2BDC = benzene-1,4-dicarboxylic acid), and Cd-2(btec)(phen)(2)(H2O)(2) (3) (H(4)btec = 1,2,4,5-benzenetetracarboxylic acid), were synthesized under different conditions by using the metal-organic coordination compound Cd(phen)(2)(NO3)(2) as the metal source instead of inorganic metal salt. Polymer 1 is a 1-D zigzag chain, which crystallizes in the monoclinic system, Cc space group. Polymer 2 is a 2-D layered network, which crystallizes in the monoclinic system, P2/c space group. The 3-D supramolecular framework 3 crystallizes in the triclinic system, P (1) over bar space group. The particular interest of 3 is two entirely independent cadmium atoms in its structure. They separately form 1-D polymeric chains, which are alternately arranged to form a 3-D supramolecular framework through interchain hydrogen bonds. Additionally, these three compounds show strong fluorescence in the solid state at room temperature.