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1.
The salt N-benzylmethylammonium dihydrogenmonophosphate monohydrate is monoclinic with the following unit cell dimensions: a = 6.356(1)Å, b = 8.385(7)Å, c = 11.472(5)Å, = 104.32(1)°, space group P21 with Z = 2. The structure consists of infinite parallel two-dimensional [110] planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than normal van der Waals interactions between the layers.  相似文献   

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3.
Crystallography Reports - The crystal structure of 4,4'-substituted phenyl benzoate CH2=C(CH3)–COO–C6H4–COO–C6H4–O–С9Н19 has been investigated by...  相似文献   

4.
Potassium and ammonium dimeric (citrato)dioxovanadium(V) hydrate K2[VO2(H2cit)]2·4H2O1 and (NH4)2[VO2(H2cit)]2·2H2O2 (H4cit=citric acid) have been prepared and characterized by X-ray structure analyses. Vanadate1 crystallizes in the monoclinic space groupP21/n (No. 14) with unit cell parameters:a=9.304(2),b=11.756(2),c=11.911(2)Å, =111.72(3)°, andD c=1.911 g/cm3,Z=2; Vanadate2 also crystallizes in the monoclinic space groupP21/n with unit cell parameters:a=9.719(2),b=11.111(3),c=11.294(2)Å, =109.03(2)°, andD c=1.781 g/cm3,Z=2. Each dimer contains a centro-symmetric planar four-member V2O2 ring with two exocyclic citrate entities coordinated by the oxygen atoms of the hydroxy-and -carboxylate ligands, while the other two -carboxylate groups remain uncomplexed. Principal dimensions of the V–O bonds are 1.986(4)av (hydroxy) and 1.980(3)Å(-carboxyl) for vanadate1, 1.988(2)av (hydroxy) and 1.974(3)Å(-carboxyl) for vanadate2.  相似文献   

5.
Abstract  The crystal structure of 2-thoiphenecarboxamide is described. The compound crystallizes in the orthorhombic Pna21 space group with unit cell parameters a = 10.044 (3) ?, b = 14.203 (4) ? and c = 15.941 (3) ?; V = 2,274.1 (10) ?3. The asymmetric unit contains four independent molecules which are linked by N–H···O hydrogen bonds. The asymmetric unit at (x, y, z) is connected with another one, produced by the a-glide plane at 0.75 along the b-axis, that lies at (x + 0.5, −y + 1.5, z) by two N–H···O hydrogen bonds and by a C–H···O weak hydrogen bond to form a one-dimensional tube. Adjacent tubes are linked by C–H···pi interactions to form a three-dimensional framework. Graphical Abstract  The crystal structure of 2-thiophenecarboxamide, contains four crystallographically independent molecular components in the asymmetric unit linked by four N–H···O hydrogen bonds and a weak C–H···O hydrogen bond and form a one-dimensional tube. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

6.
The crystal structure of [Co(Ox)(NH3)4][Bi(Edta)] ? 3H2O is determined. The crystals are monoclinic, a = 9.291 Å, b = 22.275 Å, c = 11.402 Å, β = 105.79°, V = 2270.7 Å3, Z = 4, and space group P21/c. The [Bi(Edta)]? anionic complexes are linked into polymeric chains through two Bi-O bonds with the neighboring complexes.  相似文献   

7.
The ethylenediammonium pentachlorobismuthate(III) dihydrate salt is monoclinic with the following unit cell dimensions: a = 10.902(8)Å, b = 7.926(6)Å, c = 15.199(6)Å, = 96.40(1)°, space group P21/n with Z = 4. The structure shows a layer arrangement parallel to the axis: planes of the [Bi2Cl10]4– bioctahedra alternate with planes of [NH3(CH2)2NH3]2+ dications. The [Bi2Cl10]4– bioctahedra are connected through O(W)–H··· Cl hydrogen bonds, so that infinite unidimensional chains of composition [Bi2Cl10(H2O)2] n 4n– are formed in the structure parallel to the axis. These chains are themselves interconnected by means of the N–H···Cl bonds originating from the [NH3(CH2)2NH3]2+ entities, forming a three-dimensional network.  相似文献   

8.
[(H3O)(C14H20O5)2][Me2NH2]2 [PMo12O40] · 2C14H20O5 1 was synthesized from benzo-15-crown-5 and H3PMo12O40·24H2O in N,N-dimethylformamide for the first time. 1 crystallizes in the monoclinic space group C2/c with a = 18.583(4), b = 25.510(5), c = 19.904(4) Å, = 94.66(3)° D c = 2.124 mg/m3 for Z = 4. Refinement based on 7358 observed reflections led to a R1(wR2) = 0.0378(0.0761). The complex cation, [(H3O)(C14H20O5)2]+, exhibits a sandwich structure by hydrogen-bonding in the mean distance of 2.955 Å. The anion, PMo12O40 3–, is a -Keggin structure.  相似文献   

9.
Synthesis and X-ray diffraction study of {NH2C(NHC6H5)2}3[UO2(C2O4)2(NCS)] · 1.25H2O single crystals have been performed. This compound is crystallized in the orthorhombic system, with the unit-cell parameters a = 45.2646(8) Å, b = 57.7359(11) Å, c = 7.9244(3) Å, sp. gr. Fdd2, Z = 16, V = 20 709.6(10) Å3, and R = 0.0477. The uranium-containing structural units of the crystals are one-core groups of the [UO2(C2O4)2(NCS)]3? composition, belonging to the crystallochemical group AB 2 01 M 1 (A = UO 2 +2 , B 01 = C2O 4 2? , M 1 = NCS?) of uranyl complexes. The uranium-containing complexes are connected into a three-dimensional framework owing to the electrostatic interactions with the outer-sphere cations and a system of hydrogen bonds.  相似文献   

10.
The atomic structures of two V2O5–P2O5 glasses and vitreous (v-) V2O5 were investigated by X-ray and neutron diffraction. The V=O double bond is a common characteristic of the VOn units that constitute the structures of the glasses. VO5 square pyramids with elongated bonds of ~ 0.190 nm to the pyramidal base are found for the 50V2O5–50P2O5 glass. These weaker V–O bonds are balanced in V–O–P bridges by overbonded P–O bonds. The V(IV) sites, which account for 19.7% and 35.2% of the total V sites in the 73V2O5–27P2O5 and 50V2O5–50P2O5 glasses, respectively, form similar pyramids in agreement with the structure of crystalline (VO)2P2O7. The short-range structure of v-V2O5 and the 73V2O5-27P2O5 glass is formed of mixtures of VO5 and VO4 pyramids. A significant amount of V···O distances > 0.22 nm found for all glasses belong either to linkages V=O···V or to three-coordinated O sites.  相似文献   

11.
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   

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.
Crystallography Reports - The structure and thermal properties of azobenzene derivatives R1–C6H4–N=N–C6H4–R2, where R1/R2 = CH3COO/C2H5O (I), CH2=C(CH3)COO/C2H5 (II), or...  相似文献   

14.
The crystal structure of progesterone hydroquinone monohydrate was determined by means of X-ray diffraction methods:M r=442.6, orthorhombic,P212121,a=14.680(2),b=22.725(3),c=7.334(1) Å,V a=2446.6(6) Å3,Z=4,D x=1.190 M gm–3, MoK radiation ,(MoK)=0.75 cm–1,F(000)=948. The structure was solved usingMultan;R=0.059,R w=0.059 for 2736 reflections. This progesterone molecule has the most flattenedA ring, relative to the rest of the skeleton, of all progesterone molecules studied so far. Steroid, hydroquinone, and water molecules form, by means of hydrogen bonds, two parallel chains connected with each other by hydrogen bonds.The authors thank Dr. A. Szyczewski for supplying crystals. This research was supported by the project RP.II.10 from the Polish Ministry of National Education and by PHS Grant No. DK26546.  相似文献   

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16.
[Sr(C4H2O4)(OH2)3]·H2O is monoclinic, P21/n, witha=11.476(2),b=7.027(1),c=12.344(2) Å, =115.74(3)°,V=896.67 Å3,Z=4. The Sr atom is surrounded by nine oxygen atoms which come from four different maleate anions and three water molecules. The Sr–O distances range from 2.546(2) to 2.808(2) Å. The C–O distances are equal within the standard deviation 1.263(3) to 1.258(3) Å). In the maleate anion, the planes that contain the carboxylate groups form an angle of 74.44(9)°. Both carboxylate groups deviate significantly from planarity. The different coordination modes of the carboxylate group and the extensive hydrogen bonding present are responsible for the polymeric nature of the structure.  相似文献   

17.
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   

18.
A sample of a new mineral from the oxidation zone of the hydrothermal Pb, Zn, Ag Friedrichssegen deposit (Rhineland-Palatinate, Germany) was studied by single-crystal X-ray diffraction. The parameters of the triclinic (pseudoorthorhombic) unit cell are found to be a = 8.312(1) ?, b = 14.545(1) ?, c = 18.504(2) ?, ?? = 89.71 (1)°, ?? = 90.05(1)°, ?? = 90.13(1)°, and V = 2237.3(3) ?3. The structure is solved by direct methods into the sp. gr. P1 and refined to an R factor of 10.7% using 3788 reflections with |F| > 3??(F) in the isotropic-anisotropic approximation. The crystallochemical formula of lahnsteinite (Z = 8) is [(Zn2.6Fe0.3Cu0.1)VI(OH)3][ZnIV(OH)3(H2O)][SO4] · 2H2O, where the compositions of the layer composed of Zn octahedra and isolated Zn and S tetrahedra are given in square brackets. The mineral under study is chemically and structurally similar to namuwite and is a natural analog of synthetic zinc hydroxide sulfate trihydrate.  相似文献   

19.
Crystallography Reports - The structure and thermal properties of mesomorphic phenyl benzoate CH3–C(O)–C6H4–OC(O)–C6H4–OC9H19 (I) were studied by differential scanning...  相似文献   

20.
Three new cyclohexaphosphates with general formula M0.5((C6H5CH2)2NH2)5P6O18·H2O (M=Co, Cu, Cd) are reported. They crystallize with monoclinic unit-cells and are isotropic. We have determined their structure from the salt M=Co. This later exhibits the following unit-cell parameters: a = 22.739(5), b = 17.682(3), c = 18.342(3) Å, = 91.22(1)°, Z = 4,P21/n, V = 7373 Å3, and Dx = 1.373 g cm–3. The atomic arrangement can be described as layers containing P6O18 ring anions and CoO6 octahedra spreading in the (101) planes and intercalated by the dibenzylammonium groups and the water molecules. Synthesis and characterization by X-ray diffraction, IR absorption, and TA are described.  相似文献   

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