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51.
A novel copper molybdate with mixed ligands, [{(Cu·phen)2(tp)}{(Cu·phen·H2O)2(tp)}{Mo4O14}] (phen=1,10-phenanthroline, tp=terephthalate) 1, has been hydrothermally synthesized and structurally characterized. The crystal belongs to monoclinic system, space group P21/c with a=13.1711(7), b=19.6132(10), c=13.6910(7) (A), β=117.6870(10)°, V=3131.8(3)(A)3, Z=2, C64H44Cu4Mo4N8O24, Mr=1946.99, Dc=2.065 g/cm3, F(000)=1920, μ(MoKα) (A) 2.198 mm-1, R=0.0810 and wR=0.2012 for 4233 observed reflections (Ⅰ > 2σ(Ⅰ)). The structural analysis indicates that the title compound contains a discrete tetramolybdate cluster decorated with copper complex fragments and tp ligands bridging the clusters into a wave-like layer. The hydrogen bonding between adjacent layers further extends the compound into a 3-D framework.  相似文献   
52.
A new Keggin polyoxometalate-based polymer, formulated as (Hppy)2Cu2(ppy)4[SiMo12O40] (1) ppy = 4-(5-phenylpyridin-2-yl)pyridine, had been synthesized under hydrothermal conditions. Complex 1 exhibits a one-dimensional polyoxometalate-based chain constructed from Keggin anions of [SiMo12O40]4? weakly connected by dinuclear [Cu(ppy)2] groups. This complex crystallizes in the triclinic space group P-1, a = 12.621(3) Å, b = 13.168(3) Å, c = 17.467(4) Å, α = 86.09(3)°, β = 85.35(3)°, γ = 64.10(3)°, = 2601.1(9) Å3, Z = 1. The elemental analyses, FT-IR, TG-DTA for this compound were also determined.  相似文献   
53.
Anionic clay, ZnCuCoAlNO3 and its polyoxometalate intercalates were synthesized, and were characterized by XRD, IR, 31PMAS NMR, DTA and elemental analysis. The pillared products are found to be effective catalysts for oxidation of cyclohexene with molecular oxygen under mild reaction conditions  相似文献   
54.
A Bi(Ⅲ) contained heteropolymate compound Na3H2[Ce3(H2O)18Bi2W22O76] (23H2O 1 has been synthesized. It crystallizes in the triclinic system, space group P with a = 14.370(3), b = 17.113(3), c = 24.764(5) A, α = 74.33(3), β = 77.20(3), γ = 65.29(3)o, V = 5285.3(18) A3, Z = 2, Mr = 6908.66, Dc = 4.341 g/cm3, F(000) = 6042, μ(MoKσ) = 28.543 mm-1, R = 0.0604 and wR = 0.1659 for 15788 reflections with I > 2σ(I). The structure analysis revealed that in the anionic framework of the title compound the [Bi2W22O76]14- anions are connected by Ce3+ and Na+ cations into a three dimensional network.  相似文献   
55.
An organic-inorganic hybrid compound constructed from Wells-Dawson polyanion clusters and metal-organic complex subunits, [Cu(phen)3][Cu(phen)2Cu(phen)2(P2W18O62)]·2H2O (1) has been prepared hydrothermally and characterized by elemental analysis, IR, UV, cyclic voltammetry (CV) and single-crystal X-ray diffraction. Crystal structural analysis indicates that two terminal oxygen atoms of the Wells-Dawson polyanion located in the “belt” site coordinate with Cu2+. Three Cu ions have different coordination environments: Cu1 and Cu2 are five-coordinate, while Cu3 is six-coordinate. The bisupporting polyoxoanions [Cu(phen)2Cu(phen)2(P2W18O62)]2? are polymerized into a 1D chain by hydrogen bonding interactions, then the chains are stacked into a two-dimensional structure via offset, face-to-face, π ··· π stacking interactions. CV reveals that 1 exhibits three chemically-reversible processes.  相似文献   
56.
A new inorganic-organic hybrid, [Zn(phen)2(ppy)][{Zn(phen)2}{Zn(phen)2(H2O)}{P2W18O62}]?·?2H2O (phen?=?1,10′-phenanthroline, ppy?=?2-(5-phenylpyridin-2-yl)pyridine) (1), by using pre-prepared Wells–Dawson salt α-K6P2W18O62?·?15H2O as precursor, has been synthesized under hydrothermal conditions. Compound 1 was characterized by single-crystal X-ray diffraction, elemental analyses, IR spectrum and cyclic voltammetry. Yellow crystals crystallized in the monoclinic space group P2 (1)/c with a?=?16.2450(11)?Å, b?=?17.0918(11)?Å, c?=?43.640(3)?Å, β?=?92.0060(10)°, V?=?12109.4(14)?Å3, Z?=?4. The title compound represents a novel zero-dimensional structure based on bisupporting Wells–Dawson POM: one terminal oxygen atom located in the “belt” site and another located in the “cap” site of the same hemisphere of the polyanion are coordinated by Zn2+ cations. Compound 1 also contains the isolated secondary metal complex [Zn(phen)2(ppy)]2+ with two different organic ligands phen and ppy.  相似文献   
57.
Two new Keggin templated supramolecular compounds, [Zn2(H2biim)5(SiM12O40)] · 4H2O [M = W ( 1 ), Mo ( 2 )] (H2biim = 2, 2′‐biimidazole), were synthesized under hydrothermal conditions by using the ligand 2, 2′‐biimidazole. They were characterized by single‐crystal X‐ray diffraction, elemental analyses, IR and photoluminescence spectroscopy as well as cyclic voltammetry. The two isostructural compounds are constructed by two discrete supramolecular moieties: the inorganic chains consist of Keggin anions and metal‐organic chains constructed by [Zn2(H2biim)5]4+ subunits. In the dinuclear [Zn2(H2biim)5]4+ subunit, the H2biim ligands exhibit a dual role, chelating and linking. The metal‐organic chains further construct a 3D supramolecular framework with channels, in which the Keggin‐based inorganic chains are accommodated. The electrochemical behaviors of compounds 1 and 2 bulk‐modified carbon paste electrodes ( 1 ‐CPE, 2 ‐CPE) were studied.  相似文献   
58.
Molybdenum blue dispersions were synthesized by reducing an acidic molybdate solution with glucose, hydroquinone and ascorbic acid. The influence of the H/Mo molar ratio on the rate of formation of molybdenum particles was established. For each reducing agent, were determined the rate constant and the order of the particle formation and were established the conditions for the formation of aggregative stable dispersion with the maximum concentration of particles. The dispersed phase is represented by toroidal molybdenum oxide nanoclusters, which was confirmed by the results of UV/Vis, FTIR, XPS spectroscopy and DLS.  相似文献   
59.
在水热条件下合成了一例新型的多金属氧酸盐二聚物,[Ni(enMe)2]4{[Ni(enMe)2][Ni(enMe)2(H2O)]2[Mo8ⅥV6ⅣO38(VⅤO4)]2}.8H2O(1)(enMe=1,2-丙二胺),利用元素分析、红外光谱分析、粉末X射线衍射、热重分析和单晶X射线衍射表征了其结构。结果表明,化合物(1)属于单斜晶系,P2(1)/n空间群.晶胞参数为a=1.9685(4)nm,b=1.3549(3)nm,c=2.7039(5)nm,α=90°,β=93.94(3)°,γ=90°,V=7.195(2)nm3,Z=4,Dc=2.390g/cm3,Mr=2588.4,μ=3.195mm-1,F(000)=5012,最终R1=0.0743,wR2=0.1861.与此同时,(1)是第一个具有二帽-Keggin型钼钒氧簇的二聚体,它由过渡金属部分[Ni(enMe)2(H2O)]22+连接形成{[Ni(enMe)2][Ni(enMe)2(H2O)]2[Mo8ⅥV6ⅣO38(VⅤO4)]2}8-二聚阴离子.  相似文献   
60.
A novel transition metal ion bridging bis(diphosphopentamolybdates) has been synthesized and characterized by elemental analysis,IR spectrum,UV spectrum and single-crystal X-ray diffraction.The single-crystal structure analysis shows that the compound consists of seven charge-compensating 2,2'-biimidazole cations (BIIM=2,2'-biimidazole) and one dumbbell-like [Mn(H2O)4(P2Mo5O23)2]10-heteropolyanion which is constructed by two [P2Mo5O23]6-clusters bridged through one [Mn(H2O)4]2+ cation.  相似文献   
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