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Three tartrate-bridging lanthanide-based tungstoarsenate dimers K11H13[Ln3(H2O)8(OH)2(AsW9O33)(AsW10O35(C4O6H3))]2·nH2O (Ln3+ = Eu3+ (1Eu), n = 50; Tb3+ (2Tb), n = 34; C4O6H6 = tartaric acid) and K15H9[Dy3(H2O)15(OH)2(AsW9O33)(AsW10O35(C4O6H3))]2·21H2O (3Dy) have been synthesized and further characterized by elemental analyses, X-ray powder diffraction, IR spectra, thermogravimetric analyses and single-crystal X-ray diffraction. Structural analyses indicate that all the polyanions of 1Eu–3Dy are isostructural, and are composed of two identical asymmetric sandwiched subunits [Ln3(H2O)8(OH)2(AsW9O33)(AsW10O35(C4O6H3))]12– interlinked by two tartrate ligands. Furthermore, the photoluminescence and variable-temperature magnetic properties of 1Eu, 2Tb and 3Dy have also been investigated. [ABSTRACT FROM AUTHOR]

Four transition metal complexes with Schiff base and 1,10-phenanthroline, [Cu(L)(phen)]2·C2H5OH (1), [Zn(L)(phen)]2·C2H5OH (2), [Ni(L)(phen)]2·C2H5OH (3), and [Co(L)(phen)]2·C2H5OH (4) (H2L = 1-((2-hydroxynaphthalen-1-yl)methylene)thiosemicarbazide; phen = 1,10-phenanthroline) were synthesized and characterized by physico-chemical methods. The crystal structure of1was determined by X-ray single-crystal diffraction analysis.1crystallizes in the orthorhombic space groupPbcawitha = 15.008(9),b = 16.100(10),c = 37.54(2) Å,V = 9070(10) Å3,Z = 8,GOOF = 1.002,R1 = 0.0626, andwR2 = 0.0912. The fluorescence and urease inhibitory activities of the compounds were tested. The enzymatic activity study indicated that3possessed potent inhibition againstjack beanurease, with IC50 = 1.2 ± 0.1 μM, and about 35 times more than 42.1 ± 0.4 acetohydroxamic acid as positive reference. This suggests that inhibitory efficiency of these complexes can be strongly influenced by different transition metal ions. [ABSTRACT FROM AUTHOR]

Abstract: A novel metal–organic complex [Fe(H2bpdc)]SO4 (1) has been hydrothermally synthesized (H2bpdc=2,2''-bipyridyl-5,5''-dicarboxylic acid) and structurally characterized by elemental analyses, IR spectra, powder X-ray diffraction and single-crystal X-ray diffraction, which displays the first 1-D ferrous sulfate chain functionalized by H2bpdc. Interestingly, the 3-D supramolecular structure of 1 can be constructed by means of hydrogen-bonding interactions and Fe···O short contacts. Thermogravimetric analysis indicates that 1 shows a good thermal stability and can be thermally stable up to 420°C. Magnetic measurements of 1 exhibit the existence of antiferromagentic interactions within the FeII centers. [Copyright &y& Elsevier]

Two new copper-phosphotungstate complexes [CuII(1,3-dap)2]2[CuII(1,3-dap)]2H[α-PW10.5 [image omitted]O40] (1) and [CuI(phen)2]3[α-PW12O40] (2) (1,3-dap = 1,3-diaminopropane, phen =1,10-phenanthroline) have been synthesized and characterized by elemental analyses, IR spectroscopy, UV spectroscopy, thermogravimetric analyses, fluorescence spectroscopy, X-ray photoelectron spectroscopy, and single-crystal X-ray diffraction. Single-crystal diffraction analyses indicate that both 1 and 2 consist of a saturated α-Keggin phosphotungstate fundamental building unit as polyoxoanions and several metal-organic moieties as countercations. In 1, two [Cu(1,3-dap)]2+ complex cations are capped on the polyoxoanion [PW10.5 [image omitted]O40]9- through four bridging oxygens and the other two [Cu(1,3-dap)2]2+ coordination cations are grafted on the terminal oxygens of the polyoxoanion, whereas in 2, three [Cu(phen)2]2+ complex cations are discrete. Fluorescence reveals that 2 exhibits a broad emission band at 437 nm upon excitation at 380 nm. [ABSTRACT FROM AUTHOR]

Abstract: A new β-octamolybdate-supported compound: [Ni(H2O)(2,2′-bipy)2]2[ β-Mo8O26]·4H2O·2CH3COOH was synthesized by reaction of Na2MoO4 ·2H2O, NiCl2 ·6H2O with 2,2′-bipyridine employing a conventional method and structurally characterized by IR, UV spectra, thermogravimetry and differential thermal analysis (TG–DTA) and X-ray diffraction. In the title compound, the two six-coordinated Ni2+ cations with distorted octahedral configurations are combined by a β-[Mo8O26]4− isopolyanion through two terminal oxygen atoms from the framework of the isopolyanion. It is particularly interesting that the title compound exists in a very “molecular” manner and not as an extended one-dimension chain, two-dimension layer or three-dimension structure unlike many of below-mentioned organic–inorganic compounds containing β-[Mo8O26]4− anion. [Copyright &y& Elsevier]

A cationic iridium complex [Ir(dfpmpy) 2 (pzpy)](PF 6 ) with 2-(1H-pyrazol-1-yl)pyridine as ancillary ligand has been prepared, and its crystal structure, photophysical and electrochemical properties have been investigated. In degassed CH 3 CN solution, this complex exhibits blue emission with a peak wavelength of 451 nm. Photophysical property indicates that photoluminescence of complex [Ir(dfpmpy) 2 (pzpy)](PF 6 ) originates mainly from ligand-centered 3 π → π ∗ states. In addition, solution-processed organic light-emitting diodes based on [Ir(dfpmpy) 2 (pzpy)](PF 6 ) have been fabricated. A blue light electroluminescence (484 nm) was observed and a maximum current efficiency of 1.56 cd A −1 corresponding to a maximum power efficiency of 0.33 lm W −1 , has been achieved. This demonstrates that this complex is a promising phosphor for achieving efficient electrophosphorescence in the blue light region. [ABSTRACT FROM AUTHOR]