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1.
The title compound was synthesized by the reaction of [H3O+·18-crown-6][Cl-H-Cl]·3.8 C6H5Me with two equivalents of H2O. Colorless crystals, which slowly deposited from the corresponding liquid clathrate, belong to the monoclinic space group P21/n witha=10.648(6),b=9.571(2),c=20.801(6) Å,=98.67(5)°, andD c=1.24 g cm–3 forZ=4. Refinement based on 1609 observed reflections led to a finalR value of 0.072. In the crystal structure the [H3O+·18-crown-6]+ cations are packed in layers separated by puckered sheets of [(H5O 2 + )(Cl)2].  相似文献   

2.
TeO2–WO3 (TW), TeO2–WO3–La2O3 (TWL), TeO2–WO3–La2O3–Bi2O3 (TWLB) and TeO2–ZnO–Na2O–Bi2O3 (TZNB) glasses were produced by high-purity oxide mixtures melting in platinum or gold crucible at 800 °C in the atmosphere of purified oxygen. The total content of Cu, Mn, Fe, Co and Ni impurities was not more than 0.1–0.5 ppm wt in the initial oxides and glasses. The stability of TZNB glasses to crystallization, characterized by (Tx ? Tg) value more than 150 °C, was demonstrated by DSC measurements at heating rate 10 K/min. In the case of La2O3-containing glasses the thermal effects of both crystallization and fusion of the crystallized phases were not observed. The hydroxyl groups absorption coefficients of pure tellurite glasses at the maximum of the absorption band (λ ~ 3 μm) were in the region of 0.012–0.001 cm?1. The optical absorption losses, measured by the laser calorimetry method at λ = 1.56 and 1.97 μm, did not exceed 100 dB/km.  相似文献   

3.
The X-ray crystal structure of trinuclear iron acetate [Fe3O(CH3COO)6(H2O)3]2 [ZnCl4] ? 2H2O was determined. The crystal has a ionic structure. It is monoclinic, a = 25.363(7), b = 14.533(4), c = 15.692(4) Å, β = 103.11(2)°, space group C2/c, and R = 0.0685. The structure of the cationic complex [Fe3O(CH3COO)6(H2O)3]+ is typical of trinuclear iron(III) compounds containing a μ3-O bridge: the iron atoms are situated at the vertices of an almost equilateral triangle with the O atom at the center. Each Fe atom is coordinated by four O atoms of bridging carboxy groups, the μ3-bridging O atom, and the water molecule in the trans position to the latter O atom. Mössbauer spectroscopy evidence indicates the high-spin state (S = 5/2) of the iron(III) ions.  相似文献   

4.
The reaction between Yb(III) nitrate, Ag(I) nitrate, and the diethylenetriamine pentaacetate (dtpa) ligand gives rise to a bimetallic complex. [YbAg2(dtpa)(H2O)]·3H2O is triclinic, space group P-1, with a = 8.768 (3), b = 9.862 (2), c = 13.055 (2) Å, = 75.40 (1), = 83.00 (2) and = 87.46 (2)°. Each dtpa is coordinated to one ytterbium and six silver atoms. The resulting crystal structure can be described as 2D packing. In the layers, the ytterbium atoms are connected through [Ag(COO)]2 dimers. Strong hydrogen bonds, involving the noncoordinated water molecules, ensure crystal cohesion.  相似文献   

5.
A new decavanadate with mixed cations, [Mn(H2O)6]2[N(CH3)4]2[V10O28]·2H2O (1), was crystallized from a hydrothermal reaction between MnCO3 and V2O5 in the presence of N(CH3)4Br at 100°C. The structure of 1, as determined by x-ray single crystal analysis, consists of cations and anions of hexa-aqua manganese [Mn(H2O)6]2+, tetramethyl ammonium [N(CH3)4]+ and decavanadate [V10O28]6–. The extended H-bonding between the [Mn(H2O)6]2+ and [V10O28]6– ions gives rise to a pseudo- two-dimensional network in the crystal lattice x-ray crystallographic data for 1: monoclinic P21/n, a = 9.1499(5), b = 12.8725(7), c = 18.625(1) Å, = 92.252(1)°, V = 2192.0(2) Å3, MZ = 2, and D calcd = 2.22 g cm–3.  相似文献   

6.
The crystal and molecular structure of [H3O·18-crown-6]2[ReCl6]1 is reported. Crystal data for1: trigonal, space group R ,a=13.857(2) Å,c=10.154(2) Å,D c =2.85 g/cm3,Z=3,R f =0.073,R w =0.064. The oxonium ion is observed to be crystallographically disordered lying 0.37 Å on both sides of the plane defined by the crown ether oxygen atoms. The anion resides on a crystallographic position forming a slightly distorted octahedron.  相似文献   

7.
Crystals of a new framework silicate K3Sc[Si3O9] · H2O, space group Pm21 n (nonstandard setting of space group Pmn21 = C 2v 7), are obtained under hydrothermal conditions. The structure is determined without preliminary knowledge of the chemical formula. The absolute configuration is determined. The structure is close to that of the high-temperature K3Ho[Si3O9] phase, which was obtained upon the heating of K3HoSi3O8(OH)2. This structural similarity is due to the specific conditions of synthesis and an analogous formula, where holmium is replaced by scandium. A symmetry analysis shows that the high local symmetry of a block (rod) is responsible for the first-order phase transition of both the order-disorder (OD) and displacement type. The number of structures in which the simplest and high-symmetry layers are multiplied by different symmetry elements are predicted.  相似文献   

8.
The crystal structures of [Cd(H2 Edta)(H2O)] · 2H2O (I) and [Mn(H2O)4][Mn(HEdta)(H2O)]2 · 4H2O (II) are studied by X-ray diffraction [R 1 = 0.0209 (0.0272), wR 2 = 0.0571 (0.0730) for 2551 (4025) reflections with I > 2σ(I) in I (II), respectively]. Structure I contains mononuclear [Cd(H2 Edta)(H2O)] complexes with the C 2 symmetry, and structure II contains centrosymmetric trinuclear [Mn(H2O)4][Mn(HEdta)(H2O)]2 complexes. In I and II, the protonated ligands are hexadentate (2N + 4O), and the water molecule increases the coordination number of the metal atom to seven. The acid protons participate in short intermolecular hydrogen bonds, which are symmetric in II and asymmetric in I.  相似文献   

9.
Crystallography Reports - An inorganic-organic hybrid material formulated as (C6N3H18)2[P2Mo5O23] · 6H2O, has been hydrothermally synthesized and characterized by single crystal X-ray...  相似文献   

10.
[NBu4][Br3] interacts with C6H6 to form an air-stable liquid clathrate. The tribromide anion reacts with phenol to give para-bromophenol in>95% yield. The HBr which is generated in the reaction combines with the Br anion to form [Br-H-Br]. The latter forms the basis for a new liquid clathrate, [NBu4][Br-H-Br]·n C6H6. The parent salt, [NBu4][Br3], crystallizes in the monoclinic space group C2/c witha=12.983(5),b=10.380(7),c=16.222(6) Å,=93.93(3)°, andD c =1.47 g cm–3 forZ=4. The final R value is 0.068 based on 787 observed reflections.  相似文献   

11.
Malonate-thiocyanate complex (NH4)3[UO2(C3H2O4)2(NCS)] · 2H2O is synthesized and studied by X-ray diffraction. The compound crystallizes in the monoclinic system: a = 13.9983(4) Å, b = 8.1947(2) Å, c = 16.4678(4) Å, β = 100.846(1)°, space group Cc, Z = 4, and R = 0.0158. The main structural units of the crystal are mononuclear [UO2(C3H2O4)2(NCS)]3? groups belonging to the AB 2 01 M 1 crystal chemical group of uranyl complexes (A = UO 2 2+ , B 01 = C3H2O 4 2? , M 1 = NCS?). Discrete uranium-containing groups are connected by electrostatic interactions with ammonium ions and by hydrogen bonds. Some specific structural features of crystals containing [UO2(L)2(NCS)]3? complexes, where L is the oxalate or malonate ion, are discussed.  相似文献   

12.
The synthesis and crystal structure of a new microporous zincophosphate are described. [H2N2C6H16]0.5[Zn2(PO4)(HPO4)(H2O)]·H2O crystallizes in the triclinic space group P1¯ with a = 8.822(4), b = 9.236(4), c = 8.451(3) Å, = 67.19(3), = 91.32(3), = 111.10(3)°, V = 586.7(4) Å3 and Z = 2. This new material consists of infinite two-dimensional anionic layers alternated with planes containing organic diprotonated templates, N, N, N, N-tetramethylethylenediamine [H2N2C6H16]2+ molecules. The framework structure is built up of ZnO4, ZnO3OH2, PO4, and PO3OH tetrahedra, linked through oxygen vertices. The presence of terminal OH2 and OH groups, leads to an open structure containing four- and eight-rings. The organic molecules are interconnected to the framework through hydrogen bonds.  相似文献   

13.
The crystal structure of tylophorine (Chemical name 2,3,6,7 tetramethoxy phenanthro [9,10:6, 7] indolizidine. Contribution No. 0871.) methiodide monohydrate has been determined. C25H30NO 4 + I·H20, triclinic, P,a=8.831(1)Å, b=10.842(2),c=13.902(2), =105.0(1)o, =104.7(1), =97.3(1),V=1210.22Å3, Z=2,D x =1.428 g./cm–3, (CuK)=1.54184Å, (CUK)=107.2 cm–1, F(000)=544,T=295oK,R=0.038,Rw=0.046, for 2331 observed reflections withI2(I). Apart from van der Waals forces, the structure is stabilized by two hydrogen bonds of the type Ow(H) ... O and Ow(H) ... I involving the water molecule as the donor and atom O4 of the methoxy group and I as acceptors.  相似文献   

14.
A new polar hexaborate, K3[B6O10]Br (space group R3m), is synthesized under hydrothermal conditions. The radical anion is composed of macallisterite hexaborate blocks 6[3Δ + 3T] formed by boron triangles and boron tetrahedra. The blocks are joined together through vertices into a [B6O10] ∞∞∞ 2? zeolite-like framework of a new type. Large K+ cations and Br? anions are located in extended channels that are aligned parallel to rhombohedral translations of the crystal lattice. The structure of the sublattice formed by large ions consists of BrK6 bromo-centered octahedra, which are linked together through vertices into a hexagonally distorted perovskite framework. The perovskite framework is inserted into the boron-oxygen framework so that these two frameworks do not intersect. The nonlinear optical properties of powdered samples of the K3[B6O10]Br compound are investigated using the second harmonic generation method. It is found that the K3[B6O10]Br compound exhibits a high nonlinear optical activity that exceeds the activities of the majority of borate compounds and is characteristic of haloid borates of the hilgardite family.  相似文献   

15.
A water soluble flavonoid sulfate, [Ni(H2O)6](C19H17O9S)2·2H2O was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. The crystal of it belongs to triclinic crystal system, space group P–1. The results show that the title compound consists of [Ni(H2O)6]2+, C19H17O6SO3 and H2O. Ni(II) is located on the symmetry center and octahedrally coordinated by six water molecules. A variety of hydrogen bonds among [Ni(H2O)6]2+, C19H17O6SO3 and the lattice water molecules build a hydrophilic region. Aromatic ππ stacking interactions assemble isoflavone skeletons into a column and the columns form a hydrophobic region of the title compound. The sulfo-groups bridge the hydrophilic regions and the hydrophobic regions as well as the inorganic components and organic components. Hydrogen bonds, stacking interactions and the electrostatic interactions between cation [Ni(H2O)6]2+ and anion sulfonate C19H17O6SO3 lead the moieties to a three-dimensional structure.  相似文献   

16.
Crystallization of calcium nitrate from a toluene solution of triethyleneglycol (= 2,2-[1,2-ethanediylbis(oxy)]-bisethanol) resulted in the formation of the 1:2 solvate [Ca(triethyleneglycol)2](NO3)2·H2O. [Ca(C6H14O4)2](NO3)2·H2O is monoclinic, P21/c, a = 15.775(1), b = 8.660(2), c = 16.342(1) Å, = 91.239(7)°, V = 2232.1(6) Å3, Z = 4, and D c = 1.429 g cm–3. The eight-coordinate calcium has square antiprismatic geometry with two triethyleneglycol molecules straddling the metal center. The nitrate anions and water of crystallization are involved in hydrogen bonding with the alcoholic hydrogen atoms.  相似文献   

17.
以芒柄花素为先导化合物,合成了水溶性的[Co(H2O)6](C18H15O4SO3)2·4H2O,并采用IR, 1H NMR, TG-DTA, XRD和单晶X射线衍射法对其结构进行了表征.单晶X射线衍射结果表明:[Co(H2O)6]2+、C18H15O4SO 3和H2O之间存在多种氢键,形成晶体结构中的亲水区.异黄酮骨架间反平行排列,面对面和边对面芳香堆积作用同时存在于其中,构成晶体结构中的疏水区.磺酸根是连接亲水区和疏水区的桥梁.氢键、芳香堆积作用以及阴阳离子之间的静电引力共同将标题化合物组装成具有三维网络结构的超分子.  相似文献   

18.
The X-ray crystal structure of 7-hydroxyflavone monohydrate, C14H10O3 · H2O, is determined. The compound crystallizes in the monoclinic space group, P21/n with a = 3.801(3), b = 19.665(4), c = 16. 039(6), = 93.69(3)°, and = 0.68 mm–1 for Z = 4. The phenyl ring of the flavone moiety is rotated 18.6(1)° out of the penzopyran plane, which is a typical value for flavones. In the crystal lattice, there are wide channels which are lined mainly by C–H groups. The water molecules enclosed in these channels are severely disordered.  相似文献   

19.
The crystalline dihydrate and hydrochloride trihydrate of a new betaine, namely, L·2H2O (1) and [L2H]Cl·3H2O(2) (L=p-Me2NC5H4N+CH2CO2), have been synthesized and characterized by X-ray crystallography. Molecule L in compound1 [space groupPbcn, witha=15.732(3),b=7.894(2),c=18.304(4) Å, andZ=8] possesses approximateC s symmetry. The formation of hydrogen bonds by water molecules bridging neighboring carboxy oxygen atoms leads to an infinite two-dimensional network composed of a packing of two different kinds of 12-membered rings. In compound2 [space group PT witha=7.341(2),b=9.543(2),c=17.010(4) Å, =82.43(2)°, =80.34(2)°, =74.05(2)°, andZ=2], the carboxylate groups of a pair of betaine molecules are bridged by a proton to form a dimeric cation L2H+ with a very strong asymmetric hydrogen bond of length 2.464(7) Å. The crystal structure features a hydrogen-bonded corrugated ribbon comprising an alternate arrangement of edge-sharing centrosymmetric (H2O)4(Cl)2 and (H2O)4 rings running parallel to thea axis.  相似文献   

20.
Crystals of a new aqueous rare earth borate Sm3[B13O22(OH)3](OH) · 3H2O, space group P2/c, are obtained under hydrothermal conditions. The structure is determined by the heavy-atom method without preliminary knowledge of the chemical formula. The anionic radical is a boron-oxygen sheet in which two corrugated layers are related by centers of inversion. An independent layer is akin to pentaborate layers; it differs from the layer in (Nd0.925Na0.075)Nd[B9O15(OH)2]Cl0.85 · 2.65H2O by an additional branch in the form of a 4: (3[2?? + 1T] + 1??) group. The intersheet space and large holes of the sheet accommodate Sm atoms, (OH) groups, and water molecules. The new Sm-borate and the related Nd-borate are polyborates (megaborates) with complex anionic radicals. In the Sm-borate, the new two-dimensional [B13O22(OH)3]??? complex anionic radical of the 13{(4: [2T + 2??])?? + (5: [3T + 2??] + 4: (3[2?? + 1T] +1??))??}??? formula is built of three different blocks, unlike the [B9O15(OH)2]??? radical of the 9{(4: [2T + 2??])?? + (5: [3T + 2??])??}??? formula in the Nd-borate, which consists of two blocks. The rule of the inverse relationship between the polymerization degrees of the boron-oxygen radical and rare earth polyhedra holds for both borates.  相似文献   

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