Syntheses, crystal structures, and properties of four coordination polymers with a new bifunctional ligand.

Four new coordination polymers, {[Cd 2 (L) 2 ·H 2 O]·4DMF·14H 2 O} n ( 1 ), {[Cd (L)]·2DMF·6H 2 O} n ( 2 ), {[Zn 2 (L) 2 ]·4DMF·5H 2 O} n ( 3 ) and {[Cu (L)]·2DMF} n ( 4 ) (H 2 L = 2,5-bis((4H-1,2,4-triazol-4-yl)carbamoyl)terephthalic acid), have been synthesized under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction. All of them exhibit three-dimensional structures possessing one-dimensional channels filled with solvent molecules. 1 is a 3D framework with large 1D channels (6.60 × 8.56 Å 2 ) filled with free DMF molecules and the 3D structure of 1 is a new (4, 8) network with Schläfli symbol {4 16 .6 12 }{4 4 .6 2 } 2 . 2 and 3 with different metal centers have similar structure except for the numbers of free water molecules. They both feature a (4, 4)-connected 3D network of {6 5 .10} {6 5 .8} topology with left- and right-handed helical chains along b -axis. While 4 is a 3D framework with typical CdSO 4 topology. In addition, 1 – 3 show strong fluorescent emissions at room temperature, which can be assigned to the ligand-to-ligand charge transfer (LLCT) emissions. [ABSTRACT FROM AUTHOR]