1-D chain Cd(II) compound based on flexible phenylenediacetic ligand: synthesis, crystal structure, and fluorescent properties

Abstract

A coordination polymer of CdII with a flexible ligand in [Cd(Hpda)2(4,4′-bipyridyl)2] · (H2O)2 (1) (H2pda = 1,2-phenylenediacetic acid) has been synthesized by hydrothermal reactions and characterized by IR, TG, fluorescent spectrum, X-ray powder diffraction, and single-crystal X-ray diffraction techniques. The results show that 1 is monoclinic, with space group P2(1)/c, a = 1.1704(7), b = 1.7206(1), and c = 2.2073(1) nm, β = 120.881(2)°. In 1, the Cd(II) ions are linked by 4,4′-bipyridyl ligands to form 1-D chain with the arms of 1,2-pda ligands. These chains are imbedded into each other to form 2-D supramolecular sheets through hydrogen bonds. Adjacent 2-D sheets are assembled to 3-D network architecture through the crystallization of water molecules. Photoluminescence properties of 1 were investigated in the solid state at room temperature. The spectrum shows intense photoluminescence at 300 nm (λex = 275 nm).