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1.
A transition metal substituted polyoxotungstate,[Cu(en)2(H2O)]2{PW11.5Cu0.5O40 [Cu(en)2]}·2H2O1 based on Keggin frameworks ,has been hydrothermally synthesized and charac-terized by IR,TGA and single-crystal X-ray structural analysis.It is interesting to find that the structure unit contains two different valence cations,namely,one[Cu(1)(en)2(H2O)] and one [Cu(2)(en)2(H2O)]2 .Data for the crystal:orthorhombic system,space group Pbca,a=21.585(2),b=20.695(2),c=26.137(3)(A),V=11675(2)(A)3,Z=8,Mr=3428.23,Dc=3.901 g/cm3,F(000)=12156,μ(MoKα)=23.932mm-1,the final R=0.0468 and wR=0.0969 for 6927 observed reflections(Ⅰ>2σ(Ⅰ)).  相似文献   

2.
A novel germanotungstate derivative based on the dysprosium cation and monovacant Keggin anion, [Cu(en)2]2[Cu(en)2(H2O)]2H3{[Cu(en)2]2[Na2(H2O)1.75][K(H2O)3][Dy2(H2O)2(GeW11O39)3]} · 6H2O(en = ethylenediamine) 1, has been synthesized by hydrothermal method and characterized by elemental analysis, IR-UV spectroscopy, thermal analysis and single-crystal X-ray diffraction. In the compound, one kind of clusters with the Dy3+/[GeW11O39]8? ratio of 2:3 was observed. Especially, the 2:3 type displays the novel cluster based on the rare earth and monolacunary Keggin polyoxometalate.  相似文献   

3.
Abstract  A novel polyoxotungstate H5[Cu(en)2H2O]{Cu(en)2[P2W19O69(H2O)]} · 2.5H2en · 8H2O (1) has been synthesized under hydrothermal conditions and characterized by IR spectroscopy, elemental analysis, and single crystal X-ray structural analysis. Crystal data for 1: Triclinic, P-1, a = 12.673(6) ?, b = 20.147(10) ?, c = 20.514(11) ?, α = 110.432(7)°, β = 90.171(5)°, γ = 97.502(6)°, V = 4859(4) ?3, Z = 2. Compound 1 exhibits a 1D linear structure, in which the [Cu(en)2]2+ ions act as the linkages of {P 2 W 19 } lacunary units. Graphical Abstract  A novel polyoxotungstate H5[Cu(en)2H2O]{Cu(en)2[P2W19O69(H2O)]} · 2.5H2en · 8H2O has been made under hydrothermal conditions. Compound 1 exhibits a 1D linear structure based on the {P 2 W 19 } lacunary units linked by the [Cu(en)2]2+ bridging groups.   相似文献   

4.
A polyoxoniobate, [Cu(en)2]4{[Nb6O19H2]K(H2O)5}2 ? (H2en) ? 17H2O (en = ethylenediamine) (1), has been synthesized and characterized by elemental analysis, IR, XPS, TGA, and single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system, space group P 1, with a = 12.3533(16) Å, b = 12.7188(16) Å, c = 29.626(4) Å, α = 93.235(2)°, β = 96.094(1)°, γ = 106.098(2)°, V = 4429.0(10) Å3, Z = 2. The polyoxoanion is composed of a Lindqvist-type [Nb6O19H2]6? dimer bi-bridged via two K+. K+ is 10-coordinate with 10 oxygens, three from one [Nb6O19H2]6?, one from a terminal oxygen of another [Nb6O19H2]6? moiety, and the other six from water molecule. Adjacent dimeric polyoxoanions are linked to form an infinite 1-D chain via O–H ··· O hydrogen-bonding interactions which exist between the two water trimers and the dimeric polyoxoanions.  相似文献   

5.
在室温下, 由Cu(NO3)2 、1,3 -二(4 -吡啶基)丙烷(bpp)、4,4 ’ -联苯二甲酸(H2bpdc)和2,5-噻吩二甲酸(H2tdc)制备出两种新型铜( II)配位聚合物[Cu(bpp)2(bpdc)(H2O)2]n·2nH2O, 1 和[Cu(bpp)2]n·n(tdc) 7.5nH2O, 2。两个配位聚合物均为一维线型结构,铜原子均采取变形的八面体结构,在轴线方向上的两个水分子与铜原子存在较弱的配位作用。在配合物1中,两个bpdc羧酸根离子与铜原子配位,而2中的tdc羧酸离子没有与铜原子键合,只是作为反离子平衡电荷。在两个产物中, 配体bpp具有不同的构象。热重分析表明配合物1与2分别在110°C和160°C以下是稳定的。  相似文献   

6.
The reaction of Cs4[Re6Te8(CN)6]·2H2O with Cu(en)2Cl2 in water affords crystals of a cluster complex [{Cu(H2O)(en)2}{Cu(en)2}Re6Te8(CN)6]·3H2O. The structure of the compound is determined by single crystal X-ray diffraction (a = 10.8082(4) Å, b = 16.5404(6) Å, c = 24.6480(7) Å, β = 92.696(1)°, V = 4401.5(3) Å3, Z = 4, space group P21/n, R 1 = 0.0331, wR 2 (all data) = 0.0652). In the complex, cluster [Re6Te8(CN)6]4? anions are linked by Cu2+ cations into zigzag chains through cyanide bridges. The coordination environment of the copper cations is complemented by ethylenediamine molecules. Each of the cluster anions is additionally coordinated by a terminal fragment {Cu(H2O)(en)2}.  相似文献   

7.
Two Cu(II) hydroxo succinates [Cu3(H2O)2(OH)2(C4H4O4)2]?·?4H2O (1) and [Cu4(H2O)2(OH)4(C4H4O4)2]?·?5H2O (2) and one Cu(II) hydroxo glutarate [Cu5(OH)6(C5H6O4)2]?·?4H2O (3) have been prepared and structurally characterized by single crystal X-ray diffraction methods. They feature 1D and 2D copper oxygen connectivity of elongated {CuO6} octahedra in “4?+?1?+?1” and “4?+?2” coordination geometries. Within 1, linear trimers of three edge-sharing {CuO6} octahedra are connected into copper oxygen chains, which are bridged by the anti conformational succinate anions to generate 2D layers with mono terminally coordinating gauche succinate anions on both sides. The layers are assembled into a 3D framework by interlayer hydrogen bonds with lattice H2O molecules distributed in channels. Different from 1, the principal building units in 2 are linear tetramers of four edge-sharing {CuO6} octahedra. The tetramers are condensed into copper oxygen chains and the succinate anions interlink them into a 3D framework with triangular channels filled by lattice H2O molecules. The {CuO6} octahedra in 3 are edge-shared to form unprecedented 2D inorganic layers with mono terminally coordinating glutarate anions on both sides. Interlayer hydrogen bonding interactions are responsible for supramolecular assembly of the layers into a 3D framework with lattice H2O molecules in the channels. The inorganic layers in 3 can be described as hexagonal close packing of oxygen atoms with the Cu atoms in the octahedral cavities. The title compounds were further characterized by elemental analyses, IR spectra and thermal analyses.  相似文献   

8.
钒氧化合物由于其有趣的阴离子结构和在催化反应、药物化学以及材料科学等领域中的应用而受到人们的关注[1,2].  相似文献   

9.
A transition metal substituted polyoxotungstate, [Cu(en)2(H2O)]2{PW11.5Cu0.5O40[Cu(en)2] }·2H2O
1 based on Keggin frameworks, has bccn hydrothcrmally synthesized and characterized by IR, TGA and single-crystal X-ray structural analysis. It is interesting to find that the structure unit contains two different valence cations, narncly, one [Cu(1)(en)2(H2O)]^+ and one [Cu(2)(en)2(H2O)]^2+. Data for the crystal: orthorhombic system, space group Pbca, a = 21.585(2), b = 20.695(2), c = 26.137(3)A, V = 11675(2)A^3, Z = 8, Mr = 3428.23, Dc = 3.901 g/cm^3, F(000) = 12156,μ(MoKα) = 23.932 mm^-1, the final R = 0.0468 and wR = 0.0969 for 6927 observed reflections (I 〉 2σ(I)).  相似文献   

10.
11.
在水热条件下合成了一个新的混合价配位聚合物{[Cu(en)2]2HPW9ⅥW2ⅤWⅣO40}2-[Cu(en)2H2O]2·8H2O,并对其进行了元素分析,IR,UV,TG-DSC等表征.X射线单晶衍射结果表明,化合物属于单斜晶系,P21/c空间群,晶胞参数a=1.88678(12)nm,b=2.30383(14)nm,c=2.61234(16)am,α=90°,β=95.844(1)°,γ=90°,V=11.2964(12)nm3,Z=4,Dc=3.954 g/cm3,R1=0.0975,wR2=0.2041.结构测定结果表明,聚合物中杂多阴离子骨架通过氧桥相连并形成一维无限链.热性质研究表明,形成标题化合物后杂多阴离子骨架分解温度大约在600.4℃,热稳定性较母体杂多酸明显增强.  相似文献   

12.
A new chelate ligand, 5-methyl-1H-pyrazole-3-carboxylic acid (mpca), has been synthesized. This ligand reacts with cupric sulfate to give two supramolecular compounds [Cu(mpca)2(H2O)] · 3H2O (1) and [Cu2(mpca)2(pyr)4] (Pyr = pyridine) (2), which were characterized by elemental analysis and X-ray crystal diffraction. Helical water chain and strong π–π interaction are important for the stability of the 3-D structure of these supramolecules.  相似文献   

13.
金属氧酸盐因其在医药临床、工业催化、功能材料等方面的广泛应用而引起人们的关注[1~6], 其中, 有关钒化学的研究一直很活跃, 钒具有与钼、钨明显不同的结构特性, 钒可以采取VO4, VO5和VO6方式配位, 同时, 钒的价态可以是+3, +4和+5价. 由于钒可采取多种配位方式及多种价态, 与钼酸盐和钨酸盐相比, 钒酸盐更具有结构柔顺性, 同时易形成低价或混合价态物种.在以往的文献中, 有关P-V-O体系多金属氧酸盐的水热合成的研究已有大量的报道[7], 在常规溶液合成中, 人们已对As-V-O体系进行了相对深入的研究, 而有关水热合成的研究报道却很少, 已见报道的砷钒化合物有K6*6H2O[8,9], 4-[10], 6-[11](X=SO2-3, SO2-4, H2O). 为了探究水热条件下As-V-O体系的反应特性, 我们开展了这方面的研究工作, 并取得了突破性进展. 本文采用中温水热技术合成了含有机基团的砷矾超分子化合物2**4H2O, 探讨这类化合物的非线性光学性质、催化性质及其它功能特性将是一个非常有意义的研究领域.  相似文献   

14.
Abstract

In an attempt to form new multi-dimensional structures of cyano complexes including cadmium(II) and copper(I), four new complexes were obtained successively from an aqueous solution at intervals of from a few days to a few months. The complex 1 obtained first was unstable in the atmosphere. The crystal structures of the other complexes (2–4) obtained from second to fourth were determined by single crystal X-ray structure determinations. Their crystal data are as follows: 2 Cd(H2O)2 Cu(CN)3·2H2O, monoclinic, C2/m, a = 14.038(1), b = 9.944(1), c = 7.738(1) Å, β = 116.019(7)°, Z = 4; 3 K[Cd(H2O)2Cu2(CN)5]·2H2O, triclinic, PI, a = 17.429(9), b = 16.519(7), c = 10.085(5) Å, α = 128.60(3), β = 137.44(2), γ = 45.82(2)°, Z = 4; 4 K2[Cd(H2O)Cu4(CN)8]·1.5H2O, monoclinic, C2/c, a = 19.387(2), b = 16.056(3), c = 12.663(2)Å, β = 110.419(9)°, Z = 4. The main structural feature found in the complexes is that the whole framework consists of two networks, a Cd-Cu(I)-CN complex network that has an infinite network formed with bridging cyano groups between the metal atoms and a network formed with hydrogen bonding among water molecules. The second network is connected to Cd in the Cd-Cu(I)-CN complex network via a water ligand coordinated to Cd. In 2 a planar network of [CdCu(CN)3] complexes are stacked along the c axis and the second network links the stacked complexes. 3 has a stacked structure of [Cd(H2O)2Cu(CN)5]2? in a bi-layered structure. The second network of 3, which includes K+ ions with an electrostatic interaction, spreads over the crystal, penetrating vacant spaces of the metal complex network. 4 has a double lattice structure with a pair of enantiomeric three-dimensional [Cd(H2O)Cu4(CN)8]2? complexes inter-penetrating each other. There are three structural factors for forming these framwork structures: (1) a non-planar coordination structure for Cd(II) that extends the planar structure of the Cu(I)-CN complex to a three-dimensional structure for the Cd-Cu(I)-CN complex; (2) a trigonal planar coordination structure for Cu(I) that generates vacant space in the metal complex network and makes possible hydrogen bonds to form the second network; (3) structural distortions of bridging cyano groups and a coordination structure of Cu(I) that cause variations of the metal complex network structure.  相似文献   

15.
The reaction of Na10[A-α-SiW9O34] · 18H2O with CuCl2 · 2H2O in the participation of ethylenediamine (En) under hydrothermal conditions resulted in a 2D organic-inorganic hybrid monocopper(II)-substituted Keggin silicotungstate [Cu(En)2(H2O)]2[Cu(En)2]4[Si2Cu2W22O78] · 7H2O (I), which was structurally characterized by elemental analyses, IR spectrum, UV spectrum, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. Single crystal structural analysis shows that adjacent monocopper(II)-substituted Keggin silicotungstate [Si2Cu2W22O78]12? dimeric subunits are interconnected by sharing terminal oxygen atoms to make the 1D polymeric linear chain and neighboring chains are combined with each other through [Cu(En)2]2+ connectors giving rise to an interesting 2D organic-inorganic hybrid sheet architecture with a 4-connected topology. To our knowledge, I is the rare organic-inorganic hybrid 2D polyoxometate constructed by mono-transition-metal substituted Keggin silicotungstate dimeric subunits. The photocatalytic measurement illustrates that I can to some extent inhibit the photodegradation of rhodamine-B.  相似文献   

16.
17.
Two new malonato-bridged copper(II) complexes of the composition [Cu2(mal)2(datz)2(H2O)]·5H2O (1) and [Cu2(mal)2(atz)2(H2O)]·3H2O (2) (mal = malonate, atz = 4-amino-1,2,4-triazole, datz = 3,5-diamino-1,2,4-triazole) are prepared and characterized by X-ray crystal structure determination and magnetic studies. The environment of each copper atom in 1 and 2 has distorted square pyramidal and octahedral geometries. The intrachain copper-copper separation is 6.305 Å and 3.640 Å across the carboxylates and trizolates bridges respectively for complexes 1 and 2. The magnetic properties of 1 and 2 are investigated in the temperature range 2–300 K. The overall antiferromagnetic behavior is observed in both cases.  相似文献   

18.
The thermal behaviour of Ba[Cu(C2O4)2(H2O)]·5H2O in N2 and in O2 has been examined using thermogravimetry (TG) and differential scanning calorimetry (DSC). The dehydration starts at relatively low temperatures (about 80°C), but continues until the onset of the decomposition (about 280°C). The decomposition takes place in two major stages (onsets 280 and 390°C). The mass of the intermediate after the first stage corresponded to the formation of barium oxalate and copper metal and, after the second stage, to the formation of barium carbonate and copper metal. The enthalpy for the dehydration was found to be 311±30 kJ mol–1 (or 52±5 kJ (mol of H2O)–1). The overall enthalpy change for the decomposition of Ba[Cu(C2O4)2] in N2 was estimated from the combined area of the peaks of the DSC curve as –347 kJ mol–1. The kinetics of the thermal dehydration and decomposition were studied using isothermal TG. The dehydration was strongly deceleratory and the -time curves could be described by the three dimensional diffusion (D3) model. The values of the activation energy and the pre-exponential factor for the dehydration were 125±4 kJ mol–1 and (1.38±0.08)×1015 min–1, respectively. The decomposition was complex, consisting of at least two concurrent processes. The decomposition was analysed in terms of two overlapping deceleratory processes. One process was fast and could be described by the contracting-geometry model withn=5. The other process was slow and could also be described by the contracting-geometry model, but withn=2.The values ofE a andA were 206±23 kJ mol–1 and (2.2±0.5)×1019 min–1, respectively, for the fast process, and 259±37 kJ mol–1 and (6.3±1.8)×1023 min–1, respectively, for the slow process.Dedicated to Prof. Menachem Steinberg on the occasion of his 65th birthday  相似文献   

19.
The thermal behavior and non-isothermal decomposition kinetics of [Cu(en)2H2O](FOX-7)2·H2O (en=ethylenediamine) were studied with DSC and TG-DTG methods.The kinetic equation of the exothermal process is dα/dt=(10^17.92/β)4α^3/4exp(-1.688×10^5/RT).The self-accelerating decomposition temperature and critical temperature of the thermal explosion are 163.3 and 174.8 ℃,respectively.The specific heat capacity of [Cu(en)2H2O](FOX-7)2·H2O was determined with a micro-DSC method,with a molar heat capacity of 661.6 J·mol^-1·K^-1 at 25 ℃.Adiabatic time-to-explosion was also estimated as 23.2 s.[Cu(en)2H2O](FOX-7)2·H2O is less sensitive.  相似文献   

20.
The crystals of [Cu2(Edta)(Py)2(H2O)2] · 2H2O (I) and [Cu(Im)6]{;Cu(Im)4[Cu(Edta)(Im)]2} · 6H2O (II) were isolated as a result of the reaction of an aqueous solutions of Cu2(Edta) · 4H2O with pyridine or imidazole, respectively. The crystals were studied by X-ray diffraction. The crystals of I are monoclinic, a = 12.682 Å, b = 6.788 Å, c = 14.834 Å, β = 91.44°, Z = 2, space group P21/n. The crystals of II are triclinic, a = 9.118 Å, b = 14.889 Å, c = 15.130 Å, α = 72.59°, β = 72.94°, γ = 82.54°, Z = 1, space group P{ie241-1}. In the centrosymmetric binuclear complex molecule of I, an N atom and two O atoms of the Edta ligand are coordinated to each Cu atom (Cu-N, 2.046 Å; Cu-O, 1.941 and 1.954 Å). The N atom of the pyridine molecule (Cu-N, 1.993 Å) completes the base of an elongated tetragonal pyramid (4 + 1) with the O atom of the H2O molecule in the apex (Cu-O(w), 2.244 Å). The crystals of II are built of centrosymmetric complex cations [Cu(Im)6]2+ (Cu(1)-N, 2.469, 2.021, and 2.056 Å), centrosymmetric trinuclear complex anions {;Cu(Im)4[Cu(Edta)(Im)]2}2?, and crystal water molecules. In the anion, the central fragment [Cu(Im)4]2+ (Cu(2)-N, 1.985 and 2.023 Å) is bonded to two peripheral complexes [Cu(Edta)(Im)]2? through atoms O of the Edta ligand (Cu(2)-O, 2.615 Å). In the [Cu(Edta)(Im)]2? fragment of the complex anion, the Cu(3) atom is bonded to the Edta ligand through the two N atoms and three O atoms (Cu(3)-N, 1.970 and 2.071 Å; Cu(3)-O, 1.966, 1.969, and 2.238 Å) and with the imidazole molecule, through an N atom (Cu(3)-N, 2.397 Å). The coordination polyhedra of the three copper atoms (Cu(1)-Cu(3)) in the structure of II are elongated tetragonal bipyramids (4 + 2). In the structures studied, Edta4? is a hexadentate chelating/bridging ligand. However, the coordination mode of the ligand in these structures is different: in the binuclear complex I, the Edta ligand is coordinated to each Cu atom through an N atom and two O atoms with the formation of two chelate rings (symmetric (trans) coordination mode), whereas, in the trinuclear complex II, the Edta ligand is coordinated to the Cu(2) atom through an O atom and to the Cu(3) atom through the two N atoms and three O atoms with the formation of three chelate rings (asymmetric (cis) coordination mode).  相似文献   

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