3D Framework and intense photoluminescence of a novel trinuclear cadmium(II) complex with mixed ligands

A novel trinuclear cadmium(II) supramolecular complex [Cd-3(PDA)(3)(2,2'-bipy)(3)(H2O)(2)]center dot 2H(2)O (1) (H(2)PDA= pyridine-2,6-dicarboxylic acid) has been prepared under hydrothermal condition and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic system, space group P2(1)/n with a=2.122 81 (14) nm, b=1.006 09(7) nm, c=2.830 64(19) nm, beta=108.937 0(10)degrees. The structure of the complex consists of trinuclear units with all metal centers being seven-coordinated. Cd1, Cd2 and Cd3 atoms are bridged by three carboxylate groups in dimonodentate fashion to give a trinuclear molecular building block [Cd3N9(CO2R)(6)]. Intermolecular hydrogen-bond interactions and face-to-face pi-pi stacking interactions lead the complex to a 3D supramolecular architecture. Fluorescent analyses show that the complex exhibits intense blue photoluminescence at room temperature and may be potential candidate for photoactive material. CCDC: 712746.