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1.
Single crystals of Mg pivalate hydrate, Mg(H2O)6(Piv)2 · 3H2O (HPiv = (CH3)3CCOOH) are synthesized and their structure is determined by X-ray diffraction method. The crystals are rhombic: a = 10.917(2) Å, b = 12.625(2) Å, c = 31.394(8) Å, Z = 8, space group Pbca, R 1 = 0.0525. The Mg atom has octahedral surrounding of the O atoms of water molecules (Mg-O 2.044–2.137 Å). The cationic chains of [Mg(H2O)6] 2+ lie in the voids of doubled network anionic layers of [(H2O)3(Piv)2] ∞∞ 2? . Inside the layer, the pivalate anions alternate with water molecules in the xy plane, being bonded to them by hydrogen bonds. The cationic chains and the anionic layers are united into layered packs by hydrogen bonds between coordinated water molecules and pivalate anions and between coordinated and crystal hydrate water molecules.  相似文献   

2.
The title compound, cobalt 4′,7-diethoxylisoflavone-3′-sulfonate([Co(H2O)6](X)2⋅8H2O, X = C19H17O4SO3) was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic space group P-1 with cell parameters a = 9.026(3) Å, b = 16.431(5) Å, c = 18.195(6) Å, α = 72.289(4), β = 87.498(4), γ = 82.775(5), V = 2550.1(13) Å−3, Dc = 1.419 Mg m−3, and Z = 2. The results show that the title compound consists of one cobalt cation, six coordinated water molecules, eight lattice water molecules, and two 4′,7-diethoxylisoflavone-3′-sulfonate anions, C19H17O4SO3. Two anions have different conformations. Twelve H atoms of six coordinated water molecules, as donors, form hydrogen bonds with four oxygen atoms of sulfo-groups of two anions and eight oxygen atoms of eight lattice water molecules. In addition, π < eqid1 > ⋅ < eqid2 > π stacking interactions exist in the crystal structure, which together with hydrogen bonds lead to supramolecular formation with a three-dimensional network.  相似文献   

3.
Single crystals of Li(H3O)[UO2(C2O4)2(H2O)] · H2O (I) have been synthesized and studied by X-ray diffraction. Compound I crystallizes in the monoclinic crystal system with the unit cell parameters: a = 7.1682(10) Å, b = 29.639(6) Å, c = 6.6770(12) Å, β= 112.3(7)°, space group P 21/c, Z = 4, R = 4.36%. Structure I contains discrete mononuclear groups [UO2(C2O4)2(H2O)]2? ascribed to the crystal-chemical group AB 2 01 M1 (A = UO2 2+, B01 =C2O 4 2? , M1 = H2O), which are “cross-linked” by the lithium ions into infinite layers {Li(UO2)(C2O4)2(H2O)2}? perpendicular to [010]. The hydroxonium ions are located between adjacent uranium-containing layers. A hydrogen bond system involving water molecules, oxalate ions, and hydroxonium combines the anionic layers into a three-dimensional framework.  相似文献   

4.
A new neptunium(V) complex [(NpO2)2(CH3COO)2(H2O)] ? 2H2O was synthesized and its crystal structure was determined. The unit cell parameters are: a = 24.007(10) Å, b = 6.779(3) Å, c = 8.076(3) Å, space group Pnma, Z = 4, V = 1314.2(9) Å3, R = 0.049, wR(F2) = 0.105. The crystal structure of the compound is composed of neutral [(NpO2)2(CH3COO)2(H2O)] layers and molecules of the water of crystallization. Each of the crystallographically independent neptunoyl ions performs a bidentate function thus forming a composite system of cation-cation bonds.  相似文献   

5.
Single crystal X-ray diffraction study of glycine phosphite C2H5NO2·H3PO3 was performed (monoclinic, space group P21/c, a = 7.401(3) Å, b = 8.465(3) Å, c = 9.737(3) Å; β = 100.73(5)°, Z = 4). It has been found that one of hydrogen atoms is located at the centre of symmetry forming two strong hydrogen bonds to yield H4P2O 6 ?2 dimers, while another hydrogen atom is statistically disordered over two positions and organizes the dimers into an infinite corrugated chain. The ordering of this hydrogen atom position and/or displacement of the other one from the centre of symmetry will lead to the loss of symmetry centre and lowering of the point group symmetry from C2h to piezo-active group C2 or C s .  相似文献   

6.
A method for the synthesis of potassium pivalates (trimethylacetates) from potassium tert-butoxide and pivalic acid was proposed. The complexes of the formulas [K(H2O)(Piv)](I) and [K2(Phen)(H2O)2(Piv)2] (II) (Piv denotes the pivalate anion and Phen denotes 1,10-phenanthroline) were obtained and characterized by elemental analysis and IR and 1H NMR spectroscopy. The crystal structures of complexes I and II were determined using X-ray diffraction. Crystal structure I has a layered motif with two nonequivalent K atoms (C.N.s 5 + 2 and 6). The coordination of phenanthroline in II gives rise to a ribbon motif, the structure containing three nonequivalent K atoms (C.N.s 6, 6 + 1, and 8).  相似文献   

7.
The system hydrogen peroxide–hexafluoroacetone sesquihydrate effectively oxidizes adamantane in the presence of VO(acac)2 to afford 64% of adamantan-1-ol in tert-butyl alcohol or 76% of adamantan-2-one in a mixture of acetic acid with pyridine.  相似文献   

8.
Solubility isotherms of water–sulfonol–hydrochloric (or sulfuric) acid and water–sodium dodecyl sulfate–hydrochloric acid systems at 75°C and a water–sodium dodecyl sulfate–sulfuric acid system at 50°C are constructed. Regions of two-phase liquid equilibrium suitable for use in extraction are found. Concentration parameters for extraction are determined. The interfacial distribution of a series of metal ions with and without such additional complexing reagents as diantipyrylmethane and diantipyrylheptane is studied.  相似文献   

9.
Under hydrothermal conditions, the complex [Mn(lmdc)2(H2O)2] · 2H2O (I) was synthesized and characterized by elemental analysis and IR spectrum (HImdc = 4,5-imidazofedicarboxylic acid). The crystal structure of I was determined by single-crystal X-ray diffraction (crystallizing in the monoclinic crystal system, P 2/c space group, a = 11.000(2), b = 7.1281(14), c = 12.696(3) Å, β = 122.45(3), Z = 2. In I, the Mn2+ ion was chelated by two Imdc with one of their nitrogen atoms and a carboxylic oxygen atom, while two water molecules occupy the axial position of the Mn atom forming a distorted octahedral geometry. Three-dimensional structure of I was formed by intermolecular hydrogen bonds. UV-Vis and fluorescence spectra of I interacting with DNA show that insertion is the main binding mode between I and fish sperm DNA. Gel electrophoresis shows that I cleaves both supercoiled and circular pBR322 DNA to form a small molecular fragment.  相似文献   

10.
The structure of the salt Cs[Gd(H2O)4Re6Te8(CN)6]·4H2O (space group P-1, a = 9.436(5) Å, b = 12.365(7) Å, c = 15.187(8)Å, α = 89.104(10)°, β = 86.996(10)°, γ = 82.304(9)°) has been established by single crystal XRD. The structure of the compound features layers involving Gd3+ cations bound to cluster anions [Re6Te8(CN)6]4? through cyanide groups. The interlayer space contains cesium cations and crystallization water molecules.  相似文献   

11.
A new Co(III) complex of 1,2-cyclohexanedionedioxime and thiocarbamide with an SO 4 2? anion and solvation water molecules in the outer sphere has been synthesized and its structure has been defined. Orthorhombic crystals, a = 11.659(2) Å, b = 26.448(5) Å, c = 30.142(6) Å, V = 9295(3) Å 3, Z = 8, dcalc = 1.599 g/cm3, space group Pbca; final R index is 0.0578 for 8221 reflections with I > 2σ(I). In the octahedral Co(III) complex, two 1,2-cyclohexanedionedioxime residues lie in the equatorial plane, while two thiocarbamide molecules are in the axial plane. Intramolecular bonds: N-H…O and O-H…O type hydrogen bonds and π-π interactions that stabilize the complex cations. In crystal, the components are linked by N-H…O and O-H…O hydrogen bonds into a 3D framework.  相似文献   

12.
Single crystals of Cs[(UO2)2(C2O4)2(OH)] · H2O were synthesized and structurally studied using X-ray diffraction. The compound crystallizes in monoclinic space group P21/m, Z = 2, with the unit cell parameters a = 5.5032(4) Å, b = 13.5577(8) Å, c = 9.5859(8) Å, β = 97.012(3)°, V = 709.86(9) Å3, R = 0.0444. The main building units of crystals are [(UO2)2(C2O4)2(OH)]? layers of the A2K 2 02 M2 (A = UO 2 2+ , K02 = C2O 4 2? , and M2 = OH?) crystal-chemical family. Uranium-containing layers are linked into a three-dimensional framework via electrostatic interactions with outer-sphere cations and hydrogen bonds with water molecules.  相似文献   

13.
14.
A novel Salen-type bisoxime ligand, 6,6′-dimethoxy-2,2′-[(1,4-butylene)dioxybis(nitrilomethylidyne)]diphenol (H2L) and its tetranuclear Cu(II) complex, [Cu4L2(pic)4(H2O)2]·2H2O, have been synthesized and characterized by elemental analyses, IR, TG-DTA and 1H-NMR etc. The X-ray crystal structure of the complex reveals that formation of a tetranuclear structure, which consists of four copper(II) atoms, two pentadentate L2−units, four picratols, two coordinated water molecules and two crystallizing water molecules. Around four copper ions are all octahedral geometries. It was demonstrated that the picratols in the tetranuclear copper(II) complex show a novel tridentate coordination mode.  相似文献   

15.
A complex of neodymium perchloric acid coordinated with L-glutamic acid and imidazole, [Nd(Glu)(H2O)5(Im)3](ClO4)6·2H2O was synthesized and characterized by IR and elements analysis for the first time. The thermodynamic properties of the complex were studied with an automatic adiabatic calorimeter and differential scanning calorimetry (DSC). Glass transition and phase transition were discovered at 221.83 and 245.45 K, respectively. The glass transition was interpreted as a freezing-in phenomenon of the reorientational motion of ClO4 ions and the phase transition was attributed to the orientational order/disorder process of ClO4 ions. The heat capacities of the complex were measured with the automatic adiabatic calorimeter and the thermodynamic functions [H T-H 298.15] and [S T-S 298.15] were derived in the temperature range from 80 to 390 K with temperature interval of 5 K. Thermal decomposition behavior of the complex in nitrogen atmosphere was studied by thermogravimetric (TG) analysis and differential scanning calorimetry (DSC).  相似文献   

16.
Single crystals of Ba3[UO2(C2O4)2(NCS)]2 · 9H2O are synthesized and studied by X-ray diffraction. The crystals are orthorhombic, space group Fddd, Z = 16, and the unit cell parameters are a = 16.253(3) Å, b = 22.245(3) Å, c = 39.031(6) Å. The main crystal structural units are mononuclear complex groups [UO2(C2O4)2NCS]3? of the crystal-chemical family (AB 2 01 M1 (A = UO 2 2+ , B01 = C2O 4 2? , M1 = NCS?) of the uranyl complexes linked into a three-dimensional framework by electrostatic interactions and hydrogen bonds involving oxalate ions and water molecules.  相似文献   

17.
Thermogravimetry combined with evolved gas mass spectrometry has been used to characterise the mineral crandallite CaAl3(PO4)2(OH)5·(H2O) and to ascertain the thermal stability of this ‘cave’ mineral. X-ray diffraction proves the presence of the mineral and identifies the products of the thermal decomposition. The mineral crandallite is formed through the reaction of calcite with bat guano. Thermal analysis shows that the mineral starts to decompose through dehydration at low temperatures at around 139 °C and the dehydroxylation occurs over the temperature range 200–700 °C with loss of the OH units. The critical temperature for OH loss is around 416 °C and above this temperature the mineral structure is altered. Some minor loss of carbonate impurity occurs at 788 °C. This study shows the mineral is unstable above 139 °C. This temperature is well above the temperature in the caves of 15 °C maximum. A chemical reaction for the synthesis of crandallite is offered and the mechanism for the thermal decomposition is given.  相似文献   

18.
A novel organic-inorganic hybrid compound based on weak intermolecular interactions formulated as Ni(H2Bibzim)3Cl2 · 2H2O (H2Bibzim = 2,2-bibenzimidazole, formula, C14H10N4) has been synthesized under hydrothermal conditions and characterized by elemental analysis, single-crystal X-ray diffraction analyses, and IR spectra. It crystallizes in the orthorhombic system, space group Pbcn, Z = 2, a = 20.8530(19), b = 15.7838(14), c = 12.3159(11) Å, V = 4053.7(6) Å3, M r = 1736.84, ρc = 1.423g/cm3, λ = 0.71073 Å, μ(MoK α) = 0.664 mm?1, F(000) = 1792, R = 0.0283 and wR = 0.0707 for 3746 observed reflections with I > 2σ(I). The complex is composed of mononuclear cations [Ni(H2Bibzim)3]2+, chlorine anions, and lattice water molecules, which are linked into a two-dimensional supramolecular architectures via hydrogen bonds and π-π-stacking interactions.  相似文献   

19.
A new compound {[Cu(En)2]2V2O7} · 4H2O (I) (En = ethanediamine) has been synthesized by the combination of hydrothermal and solvent evaporation method and characterized by single-crystal X-ray diffraction (CIF file CCDC no. 1450218), IR, UV-Vis spectra, thermogravimetric analysis, powder X-ray diffraction, and fluorescence analysis. Crystal data for I: C8H40Cu2N8O11V2, Mr = 653.44, orthorhombic, space group Cmca, a = 18.559(11), b = 17.583(11), c = 7.600(6) Å, V = 2480(3) Å3, and Z = 4. Interestingly, two [Cu(En)2]2+ coordination cations are bridged by the [V2O7]4– unit to build up a neutral framework compound.  相似文献   

20.
A novel complex, Cu2[(Dmbiim)4H2O](ClO4)4·3H2O (Dmbiim = 1.1′-dimethyl-2.2′-biimida-zole), has been synthesized and studied by X-ray crystallography. Crystal data for CuO9N8C16Cl2H22: a = 10.160(2) Å, b = 12.991(3) Å, c = 20.646(4) Å, β = 101.443(3)°, space group P2(1)/c, Z = 4, d calc = 1.504 g/cm3, R = 0.0718. The crystal structure reveals that the complex is cage-shaped, with two Cu ions bridged by Dmbiim and each Cu ion chelated by the oxygen atom of water and four nitrogen atoms of Dmbiim.  相似文献   

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