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A silver(I) coordination polymer with mixed 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (bpz) and maleic acid, [Ag2(bpz)3(fum)]n(1, H2fum = fumaric acid), was synthesized under hydrothermal condition byin situisomerization of maleic acid to fumaric acid and characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction, TGA, and single-crystal X-ray diffraction. The maleic acidin situisomerizes to fumaric acid and participates in the formation of1. Topologically, the structure of1features a rare 3-connected twofold interpenetrateddia-fnet with a point symbol of {4.142}. Compound1exhibits photoluminescence in the solid state with an emission maximum at 470 nm upon excitation at 365 nm at room temperature, which is attributed to intraligand or/and interligandπ → π* transition. With bpz andin situgenerated fumaric acid ligands, a new polymer of [Ag2(bpz)3(fum)]nwas synthesized under hydrothermal conditions. It presents a unique twofold interpenetrated 3-D network with a raredia-ftopology. If the Ag(I)⋯Ag(I) interaction is included in the simplification of the net, each Ag(I) is a 4-connected node, thus, a non-interpenetrated 4-connectedupdnet with a point symbol of {4.63.82} is obtained. [ABSTRACT FROM PUBLISHER]

Four new fpa-metal complexes, [Co(fpa)2(H2O)2] (1), [Cu(fpa)2(H2O)] (2), [Zn2(fpa)4(bpp)2]n(3), and {[Zn(bpy)(H2O)4] · 2(fpa)}n(4), have been synthesized and fully characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction, and thermogravimetric analysis (TGA), (Hfpa = 2,2-difluoro-2-(pyridine-2-yl)acetate, bpp = 1,3-bis(4-pyridyl)propane, bpy = 4,4′-bipyridine). X-ray diffraction analyses reveal that1and2with 0-D structures are both extended into 3-D supramolecular networks through hydrogen bonds and π···π interactions. Complex3with chiral centers possesses a 1-D structure constructed by two kinds of bpp molecules and four kinds of fpa−molecules with different conformations, with bbp and fpa−bridging and capped ligands, respectively. In4, bpy links [Zn(H2O)4]2+into a 1-D polymeric cationic chain and uncoordinated fpa−compensates the framework charge. The results of TGA reveal that fpa−decomposes through two processes. Both3and4show strong fluorescence in the solid state at room temperature. [ABSTRACT FROM PUBLISHER]

Reaction of 2-methyl-imidazole-4,5-dicarboxylic acid (H3MIDC) with different salts (Zn and Mn) has led to three new HnMIDC-metal complexes varying from zero- to two-dimensional structures under hydrothermal and solvothermal conditions. The complex [Zn(H2MIDC)2(H2O)2] (1) is a 0-D complex constructed by H2MIDC- and Zn centers and the complex [Mn(HMIDC)(H2O)2] · H2O (2) is a polymeric 1-D chiral chain constructed by HMIDC2- and Mn centers connected into a 3-D supramolecular framework with a 1-D channel. The complex [Zn3(MIDC)2(H2O)2(DMF)2] · 0.5H2O (3) shows a 2-D puckered structure composed of MIDC3- and Zn. The differences of the three complexes demonstrate that reaction solvent and temperature have important effects on the structure of these complexes. Complex 3 shows strong fluorescence in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

One novel 3D cadmium coordination polymer, namely, {[Cd 2 (bptc 4 − )(ox 2 − ) 0.5 (H 2 O) 2 ] · 4.5H 2 O} n ( 1 ), has been hydrothermally synthesized through a reaction of 2,3′,4,5′-biphenyltetracarboxylic acid (H 4 bptc) with divalent cadmium salt in the presence of a second ligand (ox = oxalic acid). X-ray single crystal structure analysis reveals that tetranuclear cadmium clusters are formed by linking two Cd1 and two Cd2 ions with carboxyl groups. Each ox 2 − ligand, with a bidentate chelating mode, connects two Cd2 ions from two adjacent tetranuclear clusters to afford 1D zigzag cadmium cluster chains. Furthermore, 1D chains are connected by bptc 4 − ligands to extend a 3D framework with one-dimensional channels along the [001] direction. From a topology view, complex 1 exhibits an unprecedented 2-nodal 4, 10-connected net with the Schläfli symbol of {4 6 } 2 {4 9 . 5 12 .6 22 .7 2 }. The luminescence analyses reveal that complex 1 shows an emission maximum at 437 nm, which may be attributed to the intra-ligand transition. A red shift of 31 nm compared with H 4 bptc ligand was observed and the luminescent decay lifetime is 2.74 ns, which indicates that it might be a potential blue light-emitting candidate. In addition, it was also characterized by elemental, IR spectra, PXRD and TG analyses. [ABSTRACT FROM AUTHOR]

Two new coordination compounds, { Pb(pymt) 2 } ∞ ( 1 ) and { Pb(mpymt) 2 } ∞ ( 2 ) (pymt = pyrimidine-2-thiolate and mpymt = 4-methyl-pyrimidine-2-thione) have been synthesized under solvothermal conditions and characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. In compounds 1 and 2 , pymt − and mpymt − adopt the same coordination modes ( μ −1 κ N, S and μ 2 −1 κ N, S: 2 κ S, N) to interacted with Pb 2+ , however, different topology structures for compounds 1 and 2 are obtained. Compound 1 displays a one-dimensional (1D) ribbon with square cavity constructed from two double concentric chains of [Pb-S] ∞ and [Pb-Pyrimidine] ∞ sharing Pb1 ions. Compound 2 shows 1D polymeric single chain constructed by [Pb-S] ∞ and [Pb-methyl-pyrimidine] ∞ chains. The results revealed that the methyl groups don't influence the coordination modes of pyrimidine-2-thiolate but directed the structural variations. Moreover, the fluorescent properties of compounds 1 and 2 were investigated. [ABSTRACT FROM AUTHOR]