Syntheses, crystal structures and fluorescent properties of Cd(II), Hg(II) and Ag(I) coordination polymers constructed from 1H-1,2,4-triazole-1-acetic acid

Three new d¹⁰ coordination polymers, namely [Cd(taa)Cl]_n1, [Hg(taa)Cl]_n2, and [Ag_1.5(taa)(NO₃)_0.5]_n3 (taa=1H-1,2,4-triazole-1-acatate anion) have been prepared and characterized by elemental analysis, IR, and single crystal X-ray diffraction. Compound 1 consists of two-dimensional layers constructed by carboxyl-linked helical chains, which are further linked through carboxyl group to generate a unique 3D open framework. Topological analysis reveals that the structure of 1 can be classified as an unprecedented (3,8)-connected network with the Schläfli symbol (4.5²)₂(4².5⁸.6¹⁴.7³.8). Compound 2 manifests a doubly interpenetrated decorated α-polonium cubic network with the Schläfli symbol of (4¹⁰.6².8³). Compound 3 consists of 2D puckered layers made up of Ag centers and taa⁻ bridges. In addition, all of these compounds are photoluminescent in the solid state with spectra that closely resemble those of the ligand precursor.