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1.
The reactions of anionic molybdenum and tungsten cyanide cuboidal clusters with CuII and MnII salts afforded two new cyanide-bridged heterometallic coordination polymers with the composition [{Cu2(dien)2(CN)}2{Mo4Te4(CN)12}]?14.5H2O (1) and (H3O)3K[{Mn(H2O)2}2{Mn(H2O)2(NO3)}4{W4Te4(CN)12}2]·8H2O (2). The structures of these compounds were established by X-ray diffraction analysis. Compound 1 has a layered structure, in which the cuboidal cluster fragments {Mo4Te4(CN)12}6? are linked to the copper atoms of the dinuclear fragments {(H2O)(dien)Cu(μ-CN)Cu(dien)(H2O)} through the bridging CN groups. Coordination polymer 2 has a framework structure, in which the cluster fragments {W4Te4(CN)12}6? are linked to the manganese(II) aqua complexes of two types, viz., the dinuclear fragment {Mn(μ2-H2O)2Mn} and the tetranuclear cyclic fragment {(H2O)2Mn(μ2-NO3)}4, through the bridging CN groups.  相似文献   

2.
The redox characteristics of the ternary clathrate compound{C6H5CH2SSCH2C6H5}was studied by electrochemical measurement and quantum-chemical calculations.The cyclic voltammogram of this ternary clathrate compound in 0.1M KC1O4-DMF with a platinum electride had 2.pairs of redox peak.Both the electrochemical parameters derived from the voltammogram and the results of EHMO calculations indicate that the pair of redox peak at relatively positive potentials corresponds to the redox reaction of "Fe(Ⅲ)/Fe(Ⅱ) which is irreversible in nature,while the pair of redox peak at more negative potentials corresponds to the redox reaction of Mo(Ⅴ)/ Mo(Ⅱ) which is semi-reversible.The calculations from experiment measurements are fairly agreement with the theoretical calculations.  相似文献   

3.
The [{Mn(H2O)3}2{Re6Se8(CN)6}] · 3.3H2O complex was produced on slow evaporation of an aqueous solution containing the salt of a cluster complex K4Re6Se8(CN)6 · 3.5H2O and a 23-fold excess of Mn2+. The cluster complexes [Re6Se8(CN)6]4– are linked in a crystal into the charged coordination layers [{Mn(H2O)3}4{Re6Se8(CN)6}3]4– 2 through the Mn2+ cations. The Mn2+ cations are coordinated in a layer by three cyano nitrogen atoms of the cluster complexes; the Mn–N bond lengths are 2.13(4) and 2.21(2) Å. Each [Re6Se8(CN)6]4– anion is bonded to three manganese cations Mn(1). The anions are bonded additionally to the Mn(2) cations disordered over two close positions.  相似文献   

4.
在pH=4.5的水溶液中,Na27[NaAs4W40O140]·60H2O与NiCl2·6H2O, NaVO3·4H2O和NH4Cl反应得到了不同过渡金属离子占据S2位的新型杂多钨酸盐(NH4)21[{Na2(H2O)3}Ni(H2O)VOAs4W40O140]·53H2O,用X射线单晶衍射法和元素分析确定了其结构.晶胞参数为a=2.3305(14) nm, b=2.9467(19) nm, c=1.2671(16) nm, V=8.701(9) nm3, Z=2,空间群Pmmn.在杂多阴离子[{Na2(H2O)3}Ni(H2O)VOAs4W40O140]21-中,配体{As4W40}的1个中心位和4个S2位可以选择性地被不同的金属离子所占据,其中相对的2个S2位被Ni2+和V5+统计性地占据,每种离子占据的概率为50%;{As4W40}中的另2个S2位分别被2个Na+占据,2个Na+间通过一配位水分子桥连.讨论了标题化合物的IR, TG和磁学性质.  相似文献   

5.
Compound (H3O)2[{W6Br8}Br6] · 4H2O is synthesized by the reaction of polymeric tungsten bromide W6Br12 with hydrobromic acid in an ethanolic solution. The structure of the compound is a packing of counterions H3O+ and [{W6Br8}Br6]2? and crystallization water molecules joined with each other by an extended system of hydrogen bonds. The finely crystalline sample of the complex exhibits luminescence, whose spectrum has a broad profile from ??500 nm to more than 950 nm with a maximum at ??715 nm, with an absolute quantum yield of ??0.225. The emission is characterized by the biexponential decay with lifetimes of ??2.2 and ??8.4 ??s.  相似文献   

6.
Prior to this study no data for the solubility product of BiPO4(cr) or the complexation constants of Bi with phosphate were available. The solubility of BiPO4(cr) was studied at 23±2?°C from both the over- and under-saturation directions as functions of a wide range in time (6–309 days), pH values (0–15), and phosphate concentrations (reaching as high as 1.0 mol?kg?1). HCl or NaOH were used to obtain a range in pH values. Steady state concentrations and equilibrium were reached in <6 days. The data were interpreted using the SIT model. These extensive data provided a solubility product value for BiPO4(cr) and an upper limit value for the formation of BiPO4(aq). Because the aqueous system in this study involved relatively high concentrations of chloride, reliable values for the complexation constants of Bi with chloride were required to accurately interpret the solubility data. Therefore as a part of this investigation, existing Bi–Cl data were critically reviewed and used to obtain values of equilibrium constants for various Bi–Cl complexes at zero ionic strength along with the values for various SIT ion interaction parameters. Predictions based on these thermodynamic quantities agreed closely with our experimental data, the chloride concentrations of which ranged as high as 0.7 mol?kg?1. The study showed that BiPO4(cr) is stable at pH values <9.0. At pH values >9.0, Bi(OH)3(am) is the solubility controlling phase. Reliable values for the Bi(OH)3(am) solubility reactions involving Bi(OH)3(aq) and $\mathrm{Bi}(\mathrm{OH})_{4}^{-}$ and the formation constants of these aqueous species are also reported.  相似文献   

7.
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   

8.
The study of the metastable states, obtained by thermal quenching or by light irradiation in the [{Co(prm)(2)}(2){Co(H(2)O)(2)}{W(CN)(8)}(2)]·4H(2)O complex, is reported using powder X-ray diffraction, Raman spectroscopy, optical reflectivity, and magnetic measurements. This compound is characterized by a electron-transfer (ET) phase transition occurring between a high-temperature phase (HT phase) formed by paramagnetic Co(II)-W(V) units and a low-temperature phase (LT phase) formed by diamagnetic Co(III)-W(IV) units. Metastable phases can be induced at low temperature either by thermal quenching rapidly cooling phase named RC or by irradiation photo-induced phase named PI similar to the well-known Light-Induced Excited Spin State Trapping effect. The relaxation dynamics of the metastable phases have been studied and revealed some differences between the RC and PI phases. The sigmoidal shape of the relaxation curves in the RC phase is in agreement with the cooperative nature of the process. Thermodynamic parameters that govern the relaxation have been determined and used to reproduce the experimental Thermal-Induced Excited Spin State Trapping curve.  相似文献   

9.
在水热的条件下合成了1个标题的Mo-Ni-O异核簇合物,化学式为H34NiMo12O52(Mr=2311.10),用单晶X射线衍射方法测定了它的结构,该晶体属四方晶系,I4l/amd空间群,晶胞参数为a=15.319(2),c=30.645(3)A,V=7191.2(16)A^3,Z=4,Dc=2.135g/cm^3,μ=3.369mm^-1,F(000)=4376,1036个可观察衍射点(I>2σ(I)),最终结构偏离因子R=0.0560,wR=0.1632,S=1.002,该化合物簇阴离子笼中心是Ni^2 ,由12个MoO6八面体和4个NiO6八面体通过共角和共边构成。  相似文献   

10.
0引言 由于金属和有机配体的超分子构建的拓扑多样性和在功能材料方面的潜在应用,在近几年引起化学工作者的浓厚兴趣,成为一个热门的研究领域。众所周知,这类聚合物具有许多特殊的性能。在新功能材料如选择性催化、分子识别、超高纯度分离材料、光电材料、新型半导体材料、磁性材料等方面的开发中显示了诱人的应用前景。在早期合成这类超分子配位聚合物时,人们常使用含N配体。  相似文献   

11.
Reaction of (C2H5)2SnCl2 with the trilacunary 9-tungstoarsenate(V) [A–α–AsW9O34]9? in aqueous pH 5 medium resulted in the diethyltin-containing polyanion [{Sn(C2H5)2}3(H2O)6(A–α–AsVW9O34)]3? (1), which crystallized as a hydrated guanidinium salt, [C(NH2)3]3[{Sn(C2H5)2}3(H2O)4(A–α–AsVW9O34)]·9H2O (1a). Polyanion 1 represents the first example of a diethyltin-containing polyanion. The diethyltin groups are bound to the trilacunary Keggin units via two Sn–O(W) bonds involving edge-shared WO6 octahedra. Each Sn atom also has two terminal, cis-related water ligands, and two terminal, trans-related ethyl groups. Multinuclear (1H, 13C, 119Sn, 183W) NMR spectrometry indicated that polyanion 1 is stable in solution. Compound 1a was structurally characterized in the solid state by single-crystal XRD, FT-IR, as well as thermogravimetric and elemental analyses. Single-crystal X-ray analysis showed that 1a crystallizes in the orthorhombic system, space group P nma , with a = 23.5280(10) Å, b = 15.5435(6) Å, c = 18.6191(9) Å, V = 6809.1(5) Å3 and Z = 4. The structure of 1a is an extended 2D assembly of individual polyanion units 1 linked via Sn–O(W) bridges.  相似文献   

12.
Two new compounds containing molybdenum thiocyanide cluster anions, K6[Mo4S4(CN)12]·10H2O (1) and (18-crown-6K)8[Mo6S6(CN)16]·17.5H2O (2), were synthesized and investigated by X-ray structure analysis. Crystal data: a=11.8430(17), b=11.8430(17), c=35.170(7) , V=4932.8(14) 3, space group I41/a, Z=4, dcalc=1.563 g/cm3 for 1; a=28.7513(5), b=18.4190(3), c=20.7586(4) , =118.5982(7)°, V=9651.9(3) 3, space group C2/m, Z=4, dcalc =1.563 g/cm3 for 2. The [Mo4S4(CN)12]6- cluster anion in 1 has an ordinary structure typical of cubane transition metal complexes. In the structure of the [Mo6S6(CN)16]8- anion of 2, two crystallographically independent molybdenum atoms form a Mo6 metallocluster, represented as two edge-sharing tetrahedra.  相似文献   

13.
A three-dimensional CO(3)(2-)-bridged Mn(II)-Ru(2)(II,III) complex, Mn(4)(H(2)O)(16)H[Ru(2)(CO(3))(4)](2)[Ru(2)(CO(3))(4)(H(2)O)(2)]·11H(2)O (1), was synthesized by self-assembling Ru(2)(CO(3))(4)(3-) paddle-wheel precursors and Mn(2+) cations. It contains an unprecedented layer [Ru(2)(CO(3))(4)](n)(3n-) with (4,4) network. The ferromagnetic coupling between spin centers results in ordering below 3.0 K.  相似文献   

14.
1 INTRODUCTION Polyoxomolybdates have been of great interest due to their unique structural varieties, associated multitude of properties and applications as catalysis, medicine and material[1, 2]. One of the most impor- tant aspects is the synthesis and investigation of the materials on polyoxomolybdates containing organo- metallic groups[3~5]. Such materials can provide molecular models for heterogeneous catalysis and display cooperative effects or bifunctional catalytic activity[6]. O…  相似文献   

15.
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   

16.
《Solid State Sciences》2012,14(9):1321-1326
The crystal structure analyses of {[Er(H2O)5(Er(H2O)4)3][Mo(CN)8]3·11H2O}n (1) and {[Eu(H2O)5(Eu(H2O)4)3][Mo(CN)8]3·11H2O}n (2), show that they are not only new neutral three-dimensional rare-earth octacyanomolybdate(IV) molecular frameworks, but that they also belong to an unknown structure type having seven different nodes. To the best of our knowledge this is different to any other known molybdenum(IV) octacyanide complexes published to date. Both compounds crystallize in the triclinic system, space group P-1, and are isostructural and isotypic. The coordination polyhedra of the molybdenum atoms in the three different [Mo(CN)8]4− anions are trigonal prisms, with two additional atoms. A new bridging mode for octacyanometallates is also observed with five of the eight cyanide groups involved in bridging either three or four rare-earth atoms, while the three remaining cyanide groups are terminal and are involved in hydrogen bonding. The four rare-earth atoms in 1 and 2 have different coordination polyhedra in the form of trigonal prisms with two additional atoms. The three-dimensional structures are made up of infinite two-dimensional slabs linked by one of the rare-earth metal atoms. In both compounds, apart from the 17 coordinated water molecules, there are 11 lattice water molecules of crystallization present in the cavities of the three-dimensional frameworks. The 28 water molecules and the terminal CN groups are involved in an extensive O–H⋯O and O–H⋯N hydrogen bonding network.  相似文献   

17.
<正> INTRODUCTION. Studies of six-coordinated diorganotin(Ⅳ) compounds with octahedral geometry have been widely made, which indicate that the transor distorted trans [SnR_2] unit is common for the dialkyltin(Ⅳ) species  相似文献   

18.
《Comptes Rendus Chimie》2003,6(3):377-383
The three-dimensional cyano-bridged bimetallic compound of formula [{Co(H2O)2}2Mo(CN)8]·4 H2O is described. The single-crystal X-ray structural determination revealed that the compound has a polymeric structure based on a network of [MoIV(CN)8] units and CoII ions. Each Mo(CN)8 building block is linked to Co ions through its eight CN ligands and each CoII centre is connected to four Mo units forming a highly symmetrical three-dimensional framework with square-shaped channels running through the structure. The magnetic behaviour in the temperature range 2–300 K and spectroscopic data are reported as well. To cite this article: F. Tuna et al., C. R. Chimie 6 (2003).  相似文献   

19.
Three structurally different metallasiloxanes were formed from reactions between in situ generated suspensions of Ph2Si(OH)2/BuLi (1∶2) in tetrahydrofuran (THF) with, metal dichlorides MgCl2·2THF, CrCl2, or CoCl2 followed by toluene/Py (Py=pyridine) work-up. The X-ray structures are reported for: [Mg{O(Ph2SiO)2}2]-μ-(LiPy)-μ-{(LiPy)3(OH)(Cl)] (1) incorporating two six-membered magnesiasiloxane rings and an MgLi3O3Cl cubane fragment, [{O(Ph2SiO)2}Co{O(Ph2SiO)3}-μ-(LiPy2)2] (2) with both six-and eight-membered cobaltasiloxane rings and [Cr{O(Ph2SiO)2}2-μ-(LiPy2)2] (3) with two six-membered chromiasiloxane rings. Structure assembly in these cases is apparently dictated by the metal dichloride. The compound [{O(Ph2SiO)2}Mg{O(Ph2SiO)3}-μ-(CoClPy)2]·Py (4) is formed from [{O(Ph2SiO)2}Mg{O(Ph2SiO)3}-μ-(LiPy2)2] and CoCl2 (1∶2).  相似文献   

20.
The reaction of an aqueous solution of vanadyl sulfate VOSO4·3H2O, butylmalonic acid (H2Bumal = C4H10(COOH)2), and lithium carbonate at pH ~4–5 gave crystals of the complex Li4(VO)2(Bumal)4(H2O)8]·H2O (1). The structure of complex 1 was established by X-ray diffraction analysis. The molecule of complex 1 consists of two mononuclear bischelate dianionic units {VO(Bumal)2(H2O)} linked by four lithium ions to form the hexanuclear heterometallic {V2Li4} structure. The crystals and an ethanolic solution of compound 1 were studied by ESR spectroscopy.  相似文献   

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