Mixed ligand coordination polymers with flexible bis-imidazole linker and angular sulfonyldibenzoate: Crystal structure, photoluminescence and photocatalytic activity

Four ternary coordination polymers (CPs) namely, {[Ni(SDB)(BITMB)(H2O)]center dot H2O}(n) (CP1), {[Cd(SDB) (BITMB) (H2O)]center dot(THF)(H2O)}(n) (CP2), {[Zn-2(SDB)(2)(BITMB)]center dot(THF)(2)}(n) (CP3) and {[Co-2(SDB)(2)(BITMB)]center dot(Dioxane)(3)}(n) (CP4) composed of angular dicarboxylate SDB (4,4'-sulfonyldibenzoate) and N-donor BITMB (1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethyl benzene) have been synthesized by solvothermal reactions and characterized by single crystal X-ray diffraction and other physico-chemical techniques. CP1 possesses one-dimensional ribbon type metal-organic motifs glued together by H-bonds and pi center dot center dot center dot pi interactions, whereas CP2-CP4, exhibit non-interpenetrated sql networks supported by weak supramolecular interactions. Structural diversity of these CPs can be attributed to the coordination geometry adopted by the metal nodes, versatile coordination modes of SDB and conformational flexibility of BITMB. Solid state luminescence properties of CP1-CP4 were explored. Photocatalytic performance of all CPs for the decomposition of metanil yellow by dilute hydrogen peroxide in the presence of visible light was also investigated. 25-83% dye removal from aqueous solutions in the presence of CP1-CP4 was observed. (C) 2014 Elsevier Inc. All rights reserved.