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1.
The crystal structure of p-carboxyphenylhydrazone benzoylacetone is determined. The crystals are monoclinic, a = 13.614(4) Å, b = 11.388(2) Å, c = 20.029(6) Å, β = 104.82(2)°, V = 2339(9) Å3, Z = 8, space group C2/c, and R = 0.038 for 1622 reflections with I > 2σ(I). The crystal is built of C17H14N2O4 neutral molecules that are linked by O-H?O hydrogen bonds between the carboxyl groups into centrosymmetric pseudodimers. The effect of carboxylation of the phenylhydrazone fragment and the position of the carboxyl group on the molecular packing in the crystal is determined. The N(1)-H(1N)?O(1) intramolecular hydrogen bond (N-H, 0.94 Å; H?O, 1.87 Å; N?O, 2.59 Å; and the N-H?O angle, 133°) is formed in the molecule.  相似文献   

2.
The crystal structure of the [Zn3(HEdta)2(H2O)6] complex (I) is determined by X-ray diffraction analysis. The crystals are orthorhombic, a = 14.780 Å, b = 29.699 Å, c = 7.032 Å, Z = 4, and space group Pna21. The structural units of crystals I are trinuclear linear molecules, in which the peripheral atoms Zn(1) and Zn(2) each coordinate two N atoms and three O atoms of the HEdta 3? ligand and the O(w) atom of the H2O molecule, whereas the central Zn(3) atom coordinates four O(w) atoms of the H2O molecules and two terminal O atoms of the two HEdta 3? ligands. The HEdta 3? ligand fulfills a hexadentate chelating—bridging function. The bond lengths are as follows: Zn-O(HEdta), 2.006(4)–2.123(4) Å; Zn-N, 2.214(6) and 2.128(5) Å; and Zn-O(w), 2.006(6)–2.225(5) Å. In structure I, there is a specific contact formed by hydrogen bonds, owing to which the distance between the central atoms of individual molecules appears to be shorter than that in covalently bonded complexes.  相似文献   

3.
Two isostructural complexes of dioxonium [H5O2]+ with tetrabenzo-30-crown-10 of the compositions [(tetrabenzo-30-crown-10 · H5O2)][TaF6] (I) and [(tetrabenzo-30-crown-10 · H5O2)][NbF6] (II) are studied using X-ray diffraction. The complexes crystallize in the monoclinic crystal system (space group C2/c, Z = 4). The unit cell parameters of these compounds are as follows: a = 15.6583(12) Å, b = 15.2259(13) Å, c = 16.4473(13) Å, and β = 99.398(6)° for complex I and a = 15.7117(12) Å, b = 15.2785(15) Å, c = 16.5247(15) Å, and β = 99.398(7)° for complex II. These complexes belong to the ionic type. The dioxonium cation [H5O2]+ in the form of the two-unit cluster [H3O · H2O]+ is stabilized by the strong hydrogen bond OH?O [O?O, 2.353(4) Å] and encapsulated by the crown ether. Each oxygen atom of the dioxonium cation also forms two oxygen bonds O?O(crown). The crown ether adopts an unusual two-level (pocket-like) conformation, which provides a complete encapsulation of the oxonium associate. The interaction of the cationic complex with the anion in the crystal occurs through contacts of the C-H?F type.  相似文献   

4.
The crystal structure of vlasovite obtained from the Kipawa alkaline complex in Quebec is refined to R F = 0.053 for 1515 unique reflections with |F| > 4σ(F). The parameters of the monoclinic unit are as follows: a = 11.063(8) Å, b = 10.15(1) Å, c = 8.60(1) Å, β = 100.3(1)°, space group C2/c, and Z = 4. The X-ray diffraction, electron microprobe, and IR spectroscopic data indicate that, under X-ray radiation, the specimen suffers radiation damage, which is accompanied by a partial removal of Na atoms, incorporation of H2O molecules into the structure, and, possibly, a change in the configuration of the (Si,O) framework.  相似文献   

5.
The crystal structure of (HPhen)2S2O8 · 2H2O is studied using X-ray diffraction. The crystals are monoclinic, a = 23.716(5) Å, b = 10.220(2) Å, c = 13.103(3) Å, β = 128.03(2)°, V = 2501.6(9) Å3, Z = 4, space group C2/c, and R = 0.0745 for 1579 reflections with I > 2σ(I). The crystal is built of S2O 8 2? centrosymmetric anions, HPhen + cations, and molecules of crystallization water. Hydrogen bonds link the structural units into chains. Within a chain, stacking interactions are observed between the phenanthroline rings (the interplanar spacing between the rings is 3.8 Å, and the dihedral angle between their planes is 8°). The data of IR spectroscopy confirm the formation of the N(Phen)-H bond.  相似文献   

6.
The new indole derivative, 5,5′′-Difluoro-1H,1′′H-[3,3′:3′,3′′-terindol]-2′(1′H)-one C24H15F2N3O, is synthesized in 87% yield, and its crystal structure is determined by X-ray structure analysis. The crystals are monoclinic, sp. gr. P21/n, a = 15.4563(7), b = 10.8340(6), c = 16.4718(6) Å, β = 102.403(4)°, Z = 4. Bicyclic indole moieties form dihedral angle of 61.92(5)° with each other; the oxindole ring is twisted with respect to them at angles of 85.70(5)° and 75.62(5)°. The crystal structure is stabilized by N–H···O and C–H···O hydrogen bonds involving both the DMSO solvent molecules. In addition, one C–H···π interaction is observed.  相似文献   

7.
The molecular structure of cholest-3,5-diene-7-one (C27H42O) is determined by X-ray diffraction. The compound crystallizes in the orthorhombic crystal system (space group P212121) with unit cell parameters a = 11.281(5) Å, b = 11.350(5) Å, c= 18.518(5) Å, and Z = 4. The structure is solved by direct methods and refined to an R-value of 0.054 for 1070 observed reflections [Fo > 4σ(Fo)]. Ring A adopts a distorted half-chair conformation, ring B exists in sofa conformation, ring C acquires a chair conformation, and the five-membered ring D occurs in distorted half-chair conformation. The crystal structure is stabilized by van der Waals forces.  相似文献   

8.
The crystal structures of [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][TaF6] and [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] complex compounds are determined using X-ray diffraction analysis. The tantalum complex has two polymorphic modifications, namely, the monoclinic (I) and triclinic (II) modifications. The unit cell parameters of these compounds are as follows: a = 8.507(4) Å, b = 11.947(5) Å, c = 27.392(12) Å, β = 93.11(1)°, Z = 4, and space group P21/n for modification I; and a = 10.828(1) Å, b = 11.204(1) Å, c = 12.378(1) Å, α = 72.12(1)°, β = 79.40(1)°, γ = 73.70(1)°, Z = 2, and space group P-1 for modification II. The triclinic niobium complex [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] (III) with the unit cell parameters a = 10.796(3) Å, b = 11.183(3) Å, c = 12.352(3) Å, α = 72.364(5)°, β = 79.577(5)°, γ = 73.773(4)°, Z = 2, and space group P-1 is isostructural with tantalum complex II. The structures of all three complexes are ionic in character. The oxonium cation in complexes I–III is encapsulated by the crown ether and thus forms one ordinary and two bifurcated hydrogen bonds with the oxygen atoms of the crown ether. This macrocyclic cation is bound to the anions through the C-H...F contacts (H...F, 2.48–2.58 Å). The conformation of the macrocycle in complex I differs substantially from that in complex II (III).  相似文献   

9.
The monomeric lead(II) complex, [Pb(phen)(H2O)(NO3)2] was prepared by a hydrothermal reaction of Pb(NO3)2, nitrilotriacetic acid, NaOH, 1,10-phenanthroline, and H2O. The structure was determined by X-ray crystallography. It crystallizes in monoclinic P2(1)/n space group with the crystal cell parameters of a = 6.3568(6), b = 20.2345(19), c = 11.2722(9) Å, β = 98.337(4)°, V = 1434.6(2) Å3, and Z = 4. The crystal X-ray analysis shows that the lead atom is six-coordinated by two N atoms of phen ligand, three oxygen atoms of nitrate anions and one water molecule. Owing to the presence of a lone pair of electrons of lead atom, a significant gap occurs in the coordination geometry around Pb ion. A 3D architecture is formed through the strong hydrogen bonding and π–π stacking interactions.  相似文献   

10.
At room temperature, a new coordination polymer [Ni(tpt)(imi)3(H2O)]n was synthesized by the reaction of NiCl2?6H2O, terephthalic acid, and imidazole in aqueous solution. The structure was determined by X-ray crystallography. It crystallizes in monoclinicP21/n space group with the crystal cell parameters ofa = 9.8626(4) Å,b = 15.2498(3) Å, andc = 12.7681(3)Å, β = 90.309(2)°,V = 1920.33(10) Å3, andZ = 4. The crystal X-ray analysis shows that each nickel atom is coordinated by three imidazole ligands, two terephthalate ions, and one water molecule. Each terephthalate ion bridges two nickel atoms to form a zigzag chain. The chains are further linked together via hydrogen bonds to a three-dimensional network.  相似文献   

11.
The crystal structure of the SrFe(Edta)Cl · 5H2O (I) complex is determined. The crystals are monoclinic, a = 7.530(4) Å, b = 10.575(3) Å, c = 23.308(10) Å, β = 95.75(4)°, Z = 4, and space group P21/c. The structural units of I are infinite ribbons of the molecular type that are formed by tetranuclear fragments. A tetranuclear fragment involves the centrosymmetric positively charged dimer group [Sr(H2O)4Cl] 2 2+ at the center and the [Fe(Edta)(H2O)]? anionic complexes, which compensate for the positive charge of the dimer group, at the periphery. These constituents are bound via bridging oxygen atoms of the Edta ligands. The coordination number of the Sr atom is nine. The Sr-O bond lengths lie in the range between 2.552 and 2.766 Å, the Sr-Cl bond length is 3.216(3) Å, and the Sr?Sr distance is 4.371(1) Å. The parameters of the [Fe(Edta)(H2O)]? group are within the range of values observed in such complexes: Fe-O, 1.996–2.086(3) Å; Fe-O(w), 2.110(4) Å; and Fe-N, 2.289(4) and 2.327(4) Å. Separate ribbons are linked by hydrogen bonds involving all H2O molecules and terminal oxygen atoms of the Edta ligand.  相似文献   

12.
The copper(II) phthalate complex with nicotinamide [CuL 2(μ-Pht)(H2O)] · 0.5H2O(I) (where L is nicotinamide and Pht 2? is an anion of phthalic acid) is synthesized and investigated using IR spectroscopy and X-ray diffraction. The crystals of compound I are monoclinic, a = 13.368(2) Å, b = 7.891(3) Å, c = 20.480(2) Å, β = 108.69(2)°, Z = 4, and space group P21/c. The structural units of crystal I are linear chains formed by bridging phthalate anions and crystallization water molecules. The copper atom is coordinated by two pyridine nitrogen atoms of two nicotinamide ligands (Cu-N, 2.001 and 2.045 Å), two oxygen atoms of different phthalate anions (Cu-O, 1.964 and 2.235 Å), and the oxygen atom of the H2 O molecule (Cu-O, 2.014 Å). The coordination polyhedron of the copper atom is completed to an elongated (4 + 1 + 1) tetragonal bipyramid by the second (chelating) oxygen atom of the carboxyl group (Cu-O, 2.587 Å), which is one of the anions of phthalic acid. The linear polymer molecules are joined into complex macromolecular dimers with the closest internal contacts of the specific type. The macromolecular dimers are the main supramolecular ensembles of the crystal structure.  相似文献   

13.
The crystal structure of Zn-containing greifensteinite from the Pirineus Mine (Minas Gerais, Brazil) was refined (R = 0.045, 562 reflections with |F| > 2σ(F)). The unit-cell parameters are a = 15.941(3) Å, b = 11.877(3) Å, c = 6.625(2) Å, β = 95.09(2)°; V = 1249.4 Å3; sp. gr. C2/c; and Z = 2. The idealized formula is [Mn(Fe2+, Zn)4]Ca2Be4(PO4)6(OH)4 · 6H2O. The mineral is isostructural with the previously studied monoclinic representatives of the roscherite group from different deposits and differs from these representatives in that it contains Zn in one of two octahedral positions.  相似文献   

14.
The crystal structure of the mineral afwillite [Ca12(H2O)8][SiO4]4[SiO2(OH)2]4 from the northern Baikal region was refined in a triclinic unit cell with the following parameters: a = 16.330(2) Å, b = 5.6389(6) Å, c = 11.685(1) Å, α = 90.08(1)°, β = 126.446(2)°, γ = 89.95(1)°, and sp. gr. P1. The triclinic unit cell is related to the monoclinic unit cell determined earlier (sp. gr. Cc, a = 16.278(1) Å, b = 5.6321(4) Å, c = 13.236(1) Å, and β = 134.898(3)°) by the transformation matrix [?100/010/101]. The structural model was determined using the phase-correction procedure and refined anisotropically to R = 2.8% based on 3270 independent reflections with F > 3σ(F). The crystal-chemical formula of afwillite was revised. The characteristic features of the IR spectrum of afwillite were explained based on the structural data.  相似文献   

15.
Crystals of 3,4,5-triethoxybenzoic acid benzene solvate, 3,4,5-(C2H5O)3C6H2COOH? 0.25C6H6, are monoclinic, space group P2/c, with the cell dimensions at 100 K: a = 18.729(3), b = 10.6475(17), c = 14.390(2) Å, β = 98.410(2)°, V = 2838.7(8) Å3, and Z = 8, Z′ = 2. In the crystal structure two symmetrically independent molecules of 3,4,5-triethoxybenzoic acid form a planar dimer by two O–H?sO hydrogen bonds.  相似文献   

16.
The crystal structure of mineral bussenite, Na2Ba2Fe[TiSi2O7][CO3]O(OH)(H2O)F, found in the Khibiny massif (the Kola Peninsula) has been determined. The parameters of the triclinic unit-cell are a = 5.399(3) Å, b = 7.016(9) Å, c = 16.254(14) Å, α = 102.44(8)°, β = 93.18(6)°, γ = 90.10(7)°, sp. gr. \(P\bar 1\), R = 0.054 for 1418 reflections with |F| > 2.5σ(F). The mineral studied belongs to the family of layered titanosilicates, in which, unlike the sulfate-and phosphate-containing representatives of this family, the interlayer spaces are filled with carbonate groups.  相似文献   

17.
The crystal structure of L-serine phosphate (C3O3NH7 · H3PO4) is determined by single-crystal X-ray diffraction. The unit cell parameters are as follows: a = 9.134(5) Å, b = 9.489(5) Å, c = 4.615(5) Å, γ = 99.54(5)°, space group P21, and Z = 2. The amino group of serine is protonated by a hydrogen atom of the phosphoric acid. The H2PO 4 1? ions are linked by hydrogen bonds into infinite ribbons aligned along the twofold screw axes. The ribbons form layers alternating with layers of serine molecules, which are directly linked by hydrogen bonds.  相似文献   

18.
Single crystals of cobalt uranyl sulfate are grown. The crystal structure is established by X-ray diffraction: the orthorhombic system, sp. gr. Pmc21, a = 6.452(2) Å, b = 8.295(2) Å, c = 11.288(3) Å, R1 = 0.0303, wR2 = 0.0735 for reflections with I > 2σ(I). The structure of CoUO2(SO4)2 · 5H2O consists of infinite two-dimensional uncharged [CoUO2(SO4)2H2O]2∞ layers, which are linked to each other by hydrogen bonds.  相似文献   

19.
The crystal structure of a supramolecular system consisting of indole-2,3-dione 1-(2-oxopropyl)-3-ethylene ketal (I) and indole-2,3-dione 1-(2-oxopropyl)-3-ethylene ketal thiosemicarbazone (II) molecules that are linked together by hydrogen bonds is determined using X-ray diffraction. The crystal is monoclinic, and the unit cell parameters are as follows: a = 12.8360(3) Å, b = 10.7330(3) Å, c = 19.4610(3) Å, β = 99.566(1)°, space group P21/c, and Z = 4 (C27H29N5O7S). In molecules I and II, the indole-2,3-dione 3-ethylene ketal fragments have a virtually identical structure. The pyrrole and dioxolane fragments are spiro-linked through the carbon atom with a dihedral angle close to 90°. The adjacent pyrrole and benzene rings are coplanar to within 4.4°. In molecule II, the oxygen atom of the dioxolane fragment and the terminal nitrogen atom of the thiosemicarbazide fragment are involved in the N-HïO intramolecular hydrogen bond [3.294(2) Å]. The key role in the formation of the crystal structure is played by intermolecular hydrogen bonds of the N-H?dO, C-H?O, C-H?N, and N-H?S types.  相似文献   

20.
The crystal structure of a new highly decationated representative of the eudialyte group has been established (R = 0.055, 1734 |F|). The mineral is described by the simplified formula (H3O)9Na2(K, Ba,Sr)2Ca6Zr3[Si26O66(OH)6](OH)3Cl · H2O (Z = 3). The unit-cell parameters are a = 14.078(3) Å, c = 31.24(1) Å; V = 5362 Å3; sp. gr. R3. Being chemically and structurally related to the hydrated analogues studied previously (in particular, to potassium oxonium eudialyte), the new mineral differs from its analogues in that it has a higher degree of Na-and Fe-cation depletion. The replacement of 3/4 of Na cations by loose and mobile H3O groups results in structure destabilization, which is seen from the high values of the thermal parameters of the atoms and the loss of the symmetry plane.  相似文献   

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