Two 1D double-chain silver coordination polymers constructed by Ag-Ag bonds: Synthesis, structure and properties

Two new one-dimensional (1D) double-chain Ag(I) coordination polymers, namely: {[Ag(Hcn)(bpy)]center dot 2CH(3)OH}(n) (1), [Ag-2(Hidc)(H2O)(2)](n) (2) (Hcn = 2-hydroxycinnamate, bpy = 4,4'-bipyridine, Hidc = 4,5-imidazoledicarboxylate), were synthesized by volatilization method and characterized by single-crystal X-ray diffraction, elemental analysis, IR and UV-vis spectra. Single-crystal analyses show that although two Ag(I) CPs are both 1D double-chain structure constructed by Ag-Ag bonds, CP 1 is linear, while CP 2 is zigzagged. This difference in the structure may be due to the symmetry of the repeat unit of the Ag(I) CPs and the linkage pattern of the Ag-Ag bonds, in which the repeat unit of CP 1 is symmetric, whereas that of CP 2 is asymmetric. The fluorescence properties of the ligands and CPs 1-2 in the solid-state were studied. The fluorescence peaks of the two Ag(I) CPs were weakened compared to the ligands, which is attributed to ligand-centered fluorescence. The partial quenching of the aggregates may be due to the Ag-Ag interactions. In addition, cyclic voltammograms of CPs 1-2 indicated an irreversible Ag+/Ag couple with the order of reversibility being 1 > 2. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Two new one-dimensional double-chain Ag(I) coordination polymers were synthesized and characterized. The structures of these polymers are different, with one being linear and the other being zigzagged. The fluorescence properties of the Ag(I) coordination polymers differ from the ligands, showing weakened fluorescence peaks attributed to ligand-centered fluorescence.