Effect of solvent and temperature on the photoluminescent properties of Ag(I) complexes base on two different flexibility imidazole functionalized benzoic acid linkers

A zinc(II) coordination polymer based on a flexible bis(benzimidazole) ligand: synthesis, crystal structure and fluorescence study

A new one-dimensional Zn(II) coordination polymer, {[ZnCl2(BBM)]·CH3OH} n (2,2-(1,4-butanediyl)bis-1,3-benzimidazole [BBM]), has been obtained from the hydrothermal reaction of zinc chloride with the flexible bis-benzimidazole ligand BBM and characterized by single-crystal X-ray diffraction, elemental analysis, IR and UV–vis spectra. Structural analysis has revealed that the BBM ligand connects the Zn(II) atoms to form a square-wave chain, which is further extended into supramolecular layers through hydrogen bonds and π···π stacking interactions. Solid-state fluorescence investigations showed that the Zn(II) coordination polymer has an emission peak at 381 nm upon excitation at 330 nm, which is attributed to ligand-centered luminescence. It is only slightly red shifted as compared to the ligand but partially quenched due to the strong π···π stacking interactions.

Synthesis, structure, fluorescence, and electrochemical properties of a binuclear Ag(I) complex with 1,4-bis(benzo[d]oxazol-2-yl)butane as a ligand

Reaction of 1,4-bis(benzo[d]oxazol-2-yl)butane (BBO) with [Ag(CH3CN)4(ClO4)] afforded a new binuclear silver(I) complex, with composition [Ag2(BBO)2(ClO4)2], characterized by elemental analysis, UV/Vis and IR spectroscopy, and single-crystal X-ray diffraction. The results show that the Ag(I) complex consists of a centrosymmetric dimetallacyclic structure assembled from two Ag(I) atoms and two bridging BBO ligands. The coordination environment of silver(I) complex can be described as distorted trigonal planar, with one oxygen atom from a perchlorate anion and two nitrogen atoms from two BBO ligands. The luminescence properties of the ligand and the Ag(I) complex were studied in the solid state. The emission peaks of the Ag(I) complex are attributed to ligand-centered transitions. There is no effect of the complexation except for a partial quenching. The cyclic voltammograms of the Ag(I) complex indicated an irreversible Ag+/Ag couple.

Synthesis, crystal structure, fluorescence and antioxidant properties of a binuclear Ag(I) complex based on the SPPh3 ligand

The binuclear silver(I) complex [Ag2(η2-SPPh3)2(SPPh3)2](BF4)2 has been synthesized. Crystal analysis shows the coordination sphere around Ag(I) can be described as a three-coordinated slightly distorted planar triangular configuration with both monodentate and monoatomic bidentate bridging coordination modes for the SPPh3 ligand. The fluorescence properties of free SPPh3 and the Ag(I) complex have been studied in the solid state. The Ag(I) complex shows quasi-reversible Ag+/Ag pairs in its electrochemistry and has significant antioxidant activity against hydroxyl radicals.

A new modification of [Ag4Br4(PPh3)4]: synthesis, structure and properties

A new modification of the homometallic silver(I) cluster [Ag4Br4(PPh3)4] has been prepared and characterized by elemental analysis, UV/Vis and IR spectroscopy, and X-ray crystallography. The tetramer shows a polycyclic structure with a chair conformation. The bromine atoms adopt μ 2- and μ 3-bridging modes. The shortest Ag–Ag distance in the cluster is 3.159(2) Å, which indicates significant Ag–Ag interactions. A supramolecular structure is arranged by hydrogen bonds (C–H···Br). Cyclic voltammograms of the cluster indicate a quasi-reversible Ag+/Ag couple. The fluorescence properties of the ligand and the Ag(I) cluster were studied in the solid state. The emission peaks of the Ag(I) cluster are attributed to ligand-centered luminescence.

Engineering the proton conductivity of metal–organic hybrid materials by varying the coordination mode of the ligand

We report the adjustment of proton conductivity by varying the coordination mode of a ligand.