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The Crystal Structures of (NH4)2[ReCl6], [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN and [ReCl4(18)(Crown-6)] Brown single crystals of (NH4)2[ReCl6] are formed by the reaction of NH4Cl with ReCl5 in a suspension of diethylether. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN crystallizes as brown crystal plates from a solution of ReCl5 in acetonitrile. Lustrous green single crystals of [ReCl4(18-crown-6)] are obtained by the reaction of 18-crown-6 with ReCl5 in a dichloromethane suspension. All rhenium compounds are characterized by IR spectroscopy and by crystal structure determinations. (NH4)2[ReCl6]: Space group Fm3 m, Z = 4, 75 observed unique reflections, R = 0.01. Lattice constant at ?70°C: a = 989.0(1) pm. The compound crystallizes in the (NH4)2[PtCl6] type, the Re? Cl distance is 235.5(1) pm. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN: Space group P1, Z = 1, 2459 observed unique reflections, R = 0.12. Lattice dimensions at ?60°C: a = 859.0(1), b = 974.2(7), c = 1287.3(7) pm, α = 102.69(5)°, b? = 105.24(7)°, γ = 102.25(8)°. The structure consists of two symmetry-independent [ReCl2(CH3CN)4]+ ions with trans chlorine atoms, [ReCl6]2? ions, and included acetonitrile molecules. In the cations the Re? Cl bond lengths are 233 pm in average, in the anion they are 235 pm in average. [ReCl4(18-crown-6)]: Space group P21/n, Z = 4, 3 633 observed unique reflections, R = 0.06. Lattice dimensions at ?70°C: a = 1040.2(4), b = 1794.7(5), c = 1090.0(5) pm, b? = 108.91(4)°. The compound forms a molecular structure, in which the rhenium atom is octahedrally coordinated by the four chlorine atoms and by two oxygen atoms of the crown ether molecule.  相似文献   

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Solvent-free Synthesis of Tetramethylammonium Salts: Synthesis and Characterization of [N(CH3)4]2[C2O4], [N(CH3)4][CO3CH3], [N(CH3)4][NO2], [N(CH3)4][CO2H], and [N(CH3)4][O2C(CH2)2CO2CH3] A general procedure to synthesize tetramethylammonium salts is presented. Several tetramethylammonium salts were prepared in a crystalline state by solvent-free reaction of trimethylamine and different methyl compounds at mild conditions: [N(CH3)4]2[C2O4] (cubic; a = 1 114.8(3) pm), [N(CH3)4][CO3CH3] (P21/n; a = 813.64(3), b = 953.36(3), c = 1 131.3(4) pm, β = 90.03(1)°), [N(CH3)4][NO2] (Pmmn; a = 821.2(4), b = 746.5(3), c = 551.5(2) pm), [N(CH3)4][CO2H] (Pmmn; a = 792.8(7), b = 791.7(3), c = 563.3(4) pm) and [N(CH3)4][O2C(CH2)2CO2CH3] (P21; a = 731.1(2), b = 826.4(3), c = 1 025.2(3) pm, β = 110.1(1)°). The tetramethylammonium salts were characterized by IR-spectroscopy and X-ray diffraction. The crystal structures of the methylcarbonate and the nitrite are described.  相似文献   

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The structure of two trinuclear iron acetates [Fe3O(CH3COO)6(H2O)3]Cl· 6H2O (I) and [Fe3O(CH3COO)6(H2O)3][FeCl4] · 2CH3COOH (II) was determined by X-ray diffraction analysis. Crystals I and II are ionic and belong to the orthorhombic system with parameters a = 13.704(3), b = 23.332(5), c = 9.167(2) Å, R = 0.0355, space goup P21212 for I and a = 10.145(4), b = 15.323(6), c = 22.999(8) Å, R = 0.0752, space group Pbc21 for II. The complex cation [Fe3O(CH3COO)6(H2O)3]+ has a μ3-O-bridged structure typical for trinuclear iron (III) compounds. As shown by Mössbauer spectroscopy, the iron(III) ions are in the high-spin state. In trinuclear cations, antiferromagnetic exchange interaction takes place between the Fe(III) ions with the exchange parameter J = -26.69 cm?1 for II (Heisenberg-Dirac-Van Vleck model for D3h, symmetry).  相似文献   

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Wang  Shutao  Wang  Enbo  Hou  Yu  Li  Yangguang  Wang  Li  Yuan  Mei  Hu  Changwen 《Transition Metal Chemistry》2003,28(6):616-620
A novel organic/inorganic hybrid molybdenum phosphate, [NH3(CH2CH2)2NH3]3[NH3(CH2CH2)2NH2]Na5-[Mo6O12(OH)3(PO4)(HPO4)3]2·4H2O (1), involving molybdenum presented in V oxidation, has been hydrothermally prepared and characterized by elemental analysis, i.r., u.v.–vis., x.p.s., t.g. and single crystal X-ray diffraction. The structure of the title compound (1) may be considered to consist of two [Mo6O12(OH)3(PO4)(HPO4)3] units bonded together with NaO6 octahedra, forming dimers. Further, these dimers connect with each other through four Na+ cations as bridges, giving rise to novel one-dimensional chain-like skeleton. Piperazines exist among inorganic chains acting as charge balancing cations.  相似文献   

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(CH3)4NSbCl6 and [(CH3)4N]2SiF6 are face-centred cubic compounds at ambient temperature with a = 11.548 and 11.172 A, respectively. The vibrational spectra of these two compounds are discussed in relation to their crystal structure and other compounds containing (CH3)4N+ ions. The assignment of the observed bands is discussed. The Raman and infrared spectra of [(CH3)4N]2SiF6 show that the cations and anions are not distorted inside the crystals and are weakly hydrogen-bonded to each other. The infrared spectrum of (CH3)4NSbCl6 confirms a cubic structure for this compound at ambient temperature, in which cations are in octahedral environments and can be interpreted as being disordered groups. No evidence could be found for the existence of hydrogen bonding between cations and anions in this compound. The phase transition of (CH3)4NSbCI6 is studied by means of Raman spectroscopy. It is believed to be governed by the reorientational motions of tetramethylammonium cations and may be classified as an 'order-disorder' type.  相似文献   

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Synthesis and Crystal Structure of the Tetrameric Nitrido Complex [Cu(CH3CN)4]2[W4N4Cl14(CH3CN)2] . The title compound has been prepared by the reaction of CuCl with WNCl3 in acetonitrile solution, forming red, moisture sensitive crystals. They were characterized by IR spectroscopy and by an X-ray structure determination. Space group I2/a, Z = 4, 2 027 observed unique reflections, R = 0.049. Lattice dimensions at -80°C: a = 2 527.0, b = 971.9, c = 2 137.5 pm, β = 106.01°. The compound consists of [Cu(CH3CN)4]+ ions, which are arranged to form strands, and of anions [W4N4Cl14(CH3CN)2]2?, in which the tungsten atoms were located at the vertices of a square and are linked with one another via linear W?N? W bridges. Two of the four tungsten atoms have four chlorine atoms as terminal ligands, the other two tungsten atoms have three chlorine atoms and an acetonitrile molecule as terminal ligands.  相似文献   

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Crystal Structures of the Hexachlorometalates NH4[SbCl6], NH4[WCl6], [K(18‐crown‐6)(CH2Cl2)]2[WCl6]·6CH2Cl2 and (PPh4)2[WCl6]·4CH3CN The crystal structures of the title compounds were determined by single crystal X‐ray methods. NH4[SbCl6] and NH4[WCl6] crystallize isotypically in the space group C2/c with four formula units per unit cell. The NH4+ ions occupy a twofold crystallographic axis, whereas the metal atoms of the [MCl6] ions occupy a centre of inversion. There exist weak interionic hydrogen bridges. [K(18‐crown‐6)(CH2Cl2)]2[WCl6]·6CH2Cl2 crystallizes in the orthorhombic space group R3¯/m with Z = 3. The compound forms centrosymmetric ion triples, in which the potassium ions are coordinated with a WCl3 face each. In trans‐position to it the chlorine atom of a CH2Cl2 molecule is coordinated so that, together with the oxygen atoms of the crown ether, coordination number 10 is achieved. (PPh4)2[WCl6]·4CH3CN crystallizes in the monoclinic space group P21/c with Z = 4. This compound, too, forms centrosymmetric ion triples, in which in addition the acetonitrile molecules are connected with the [WCl6]2— ion via weak C—H···Cl contacts.  相似文献   

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1 INTRODUCTION During the past decade, a series of organic-inor- ganic hybrid compounds based on metal halide units have been prepared and studied[1]. The combination of organic and inorganic components at the mole- cular level affords us the opportunity to design new hybrid materials and modulate the properties of components[2]. As a result, some interesting proper- ties, such as non-linear optical[3], interesting magne- tic[4], efficient luminescence[2], ideal thermal and mechanical sta…  相似文献   

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利用三苯基氯化锡和对苯二甲酸二钠、哌嗪荒酸二钠在甲醇中反应 ,合成了双核有机锡 (Ⅳ )配合物 [Ph3 Sn (CH3 OH)O2 CC6H4 CO2 (CH3 OH)SnPh3 ]·2CH3 OH (1)和 [Ph3 SnS2 CN(CH2 CH2 ) 2 NCS2 SnPh3 ]·2CH3 OH (2 ) .通过元素分析、红外光谱和核磁共振氢谱对其结构进行了表征 .用X射线单晶衍射测定了这两个化合物的晶体结构 .化合物 1为单斜晶系 ,空间群P2 1/n ,a =1.5 199(5 )nm ,b =0 .90 0 0 (3)nm ,c =1.82 0 6 (6 )nm ,β =113.970 (5 )° ,Z =2 ,V =2 .2 75 5(13)nm3 ,Dc=1.413g/cm3 ,μ =1.146mm-1,F(0 0 0 ) =980 ,R1=0 .0 35 3,wR2 =0 .0 6 0 6 .化合物 2为单斜晶系 ,空间群P2 1/c,a =1.5 0 6 6 (5 )nm ,b =1.0 875 (4 )nm ,c =1.35 42 (5 )nm ,β =91.6 14(5 )°,Z =2 ,V =2 .2 178(14)nm3 ,Dc=1.498g/cm3 ,μ =1.35 1mm-1,F(0 0 0 ) =10 0 8,R1=0 .0 40 1,wR2 =0 .1148.在 1和 2的晶体中 ,锡原子呈五配位畸变三角双锥构型 .配合物 1由未配位的甲醇分子通过氢键作用形成二维网状结构  相似文献   

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[Sb(12-Crown-4)2(CH3CN)][SbCl6]3 and [Bi(12-Crown-4)2(CH3CN)][SbCl6]3, first Trications of Antimony(III) and Bismuth(III) The crown ether complexes [M(12-crown-4)2(CH3CN)][SbCl6]3 with M = Sb and Bi are formed by the reaction of antimony trichloride and bismuth trichloride, respectively, with antimony pentachloride in acetonitrile solution in the presence of 12-crown-4. They form colourless, moisture sensitive crystals, which were characterized by X-ray structure determinations and by IR spectroscopy. The complex with M = Sb was also characterized by 121Sb Mössbauer spectroscopy. Both complexes crystallize isotypically in the orthorhombic space group Pbcn with four formula units per unit cell. M = Sb: 3 483 observed unique reflections, R = 0.038. M = Bi: 2 958 observed unique reflections, R = 0.036. The compounds consist of SbCl6? ions and trications [M(12-crown-4)2(CH3CN)]3+, in which the M3+ ions are ninefold coordinated by the eight oxygen atoms of the crown ether molecules and by the nitrogen atom of the acetonitrile molecule. The lone pair of the M3+ ions has no steric effect.  相似文献   

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The binary zirconium and hafnium polyazides [PPh4]2[M(N3)6] (M=Zr, Hf) were obtained in near quantitative yields from the corresponding metal fluorides MF4 by fluoride–azide exchange reactions with Me3SiN3 in the presence of two equivalents of [PPh4][N3]. The novel polyazido compounds were characterized by their vibrational spectra and their X‐ray crystal structures. Both anion structures provide experimental evidence for near‐linear M‐N‐N coordination of metal azides. The species [M(N3)4], [M(N3)5]? and [M(N3)6]2? (M=Ti, Zr, Hf) were studied by quantum chemical calculations at the electronic structure density functional theory and MP2 levels.  相似文献   

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Reactions of Uranium Pentabromide. Crystal Structures of PPh4[UBr6], PPh4[UBr6] · 2CCl4, (PPh4)2[UBr6] · 4CH3CN, and (PPh4)2[UO2Br4] · 2CH2Cl2 PPh4[UBr6] and PPh4[UBr6] · 2CCl4 were obtained from UBr5 · CH3CN and tetraphenylphosphonium bromide in dichloromethane, the latter being precipitated by CCl4. Their crystal structures were determined by X-ray diffraction. PPh4[UBr6]: 2101 observed reflexions, R = 0.090, space group C2/c, Z = 4, a = 2315.5, b = 695.0, c = 1805.2 pm, β = 96.38°. PPh4[UBr6] · 2CCl4: 2973 reflexions, R = 0.074, space group P21/c, Z = 4, a = 1111.5, b = 2114.2, c = 1718.7 pm, β = 95.42°. Hydrogen sulfide reduces uranium pentabromide to uranium tetrabromide. Upon evaporation, bromide is evolved from solutions of UBr5 with 1 or more then 3 mol equivalents of acetonitrile in dichlormethane yielding UBr4 · CH3CN and UBr4 · 3CH3CN, respectively. These react with PPh4Br in acetonitrile affording (PPh4)2[UBr6] · 4CH3CN, the crystal structure of which was determined: 2663 reflexions, R = 0.050, space group P21/c, Z = 2, a = 981.8, b = 2010.1, c = 1549.3 pm, β = 98.79°. By reduction of uranium pentabromide with tetraethylammonium hydrogen sulfide in dichloromethane (NEt4)2[U2Br10] was obtained; (PPh4)2[U2Br10] formed from UBr4 and PPh4Br in CH2Cl2. Both compounds are extremely sensitive towards moisture and oxygen. The crystal structure of the oxydation product of the latter compound, (PPh4)2[U02Br4]· 2 CH2Cl2, was determined: 2163 reflexions, R = 0.083, space group C2/c, Z = 4, a = 2006.3, b = 1320.6, c = 2042,5 pm, β = 98.78°. Mean values for the UBr bond lengths in the octahedral anions are 266.2 pm for UBr6-, 276.7 pm for UBr62? and 282.5 pm for UO2Br42?  相似文献   

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