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1.
The crystal structure of the mineral byelorussite-(Ce) NaMnBa2Ce2Ti2Si8O26(F,OH) · H2O belonging to the joaquinite group was solved and refined to R = 0.033 based on 4813 reflections with I > σ2(I). The parameters of the orthorhombic unit cell are a = 22.301(4) Å, b = 10.514(2) Å, c = 9.669(2) Å, V = 2267.1(8) Å3, sp. gr. Ama2, and Z = 4. The structure is composed of three-layer sheets, which consist of dimers of edge-sharing Ti octahedra located between isolated four-membered [Si4O2] rings. The sheets are linked to each other by Mn 5-vertex polyhedra to form a heteropolyhedral framework. Large cavities in the framework are occupied by Na 6-vertex polyhedra, Ba 11-vertex polyhedra, and REE 9-vertex polyhedra.  相似文献   

2.
The Vickers hardness of the (010) and (001) planes in (NH4)2Ni(SO4)2 · 6H2O (ANSH) crystals has been measured. Anisotropy hardness of the first kind is revealed for the (010) plane in ANSH. The hardness anisotropy coefficient k 2 was determined to be 1.5. The temperature dependence of the microhardness of the (001) face of ANSH crystals was investigated in the temperature range from 20 to 80°C. The character of fracture of the (100), (010), and (001) planes during indentation with a spherical indenter has been qualitatively determined.  相似文献   

3.
Large single crystals of rubidium nickel hexahydrate Rb2Ni(SO4)2 · 6H2O (RNSH) of optical quality were grown for the first time. The atomic structure of RNSH crystals was refined. A comparative analysis of the crystal structures of (M 1+)2Ni(SO4)2 · 6H2O, where M 1+ is K, Rb, or Cs, was performed. The solubility curve of RNSH in water was measured. The optical and thermogravimetric properties of RNSH were investigated. The internal defect structure of RNSH crystals was studied by X-ray topography.  相似文献   

4.
The complex [(NH2)2CSSC(NH2)2]2[OsBr6]Br2 · 3H2O is synthesized by the reaction of K2OsBr6 with thiocarbamide in concentrated HBr and characterized using electronic absorption and IR absorption spectroscopy. Its crystal structure is determined by X-ray diffraction. The crystals are orthorhombic, a = 11.730(2) Å, b = 14.052(3) Å, c = 16.994(3) Å, space group Cmcm, and Z = 4. The [OsBr6]2? anionic complex has an octahedral structure. The Os-Br distances fall in the range 2.483–2.490 Å. The α,α′-dithiobisformamidinium cation is a product of the oxidation of thiocarbamide. The S-S and C-S distances are 2.016 and 1.784 Å, respectively. The H2O molecules, Br?ions, and NH2 groups of the cation are linked by hydrogen bonds.  相似文献   

5.
Abstract  A three-dimensional lanthanide metal-organic coordination polymer Yb3(BDC)4.5(DMF)2(H2O)3 · (DMF)2 has been synthesized by the reaction of the lanthanide metal ion (Yb3+) with 1,4-benzenedicarboxylic acid (H2BDC) under mild condition. The compound crystallizes in the triclinic system, space group PI with unit cell parameters a = 10.7428(9) Å, b = 11.2786(9) Å, c = 26.172(2) Å, α = 85.060(2)°, β = 88.1060(10)°, γ = 62.3670(10)°, V = 2798.9 (4) Å3, Z = 2. The crystal structure exhibits one-dimensional channels along the [011] direction. The fluorescent results showed that there were two emission peaks at 375 and 420 nm when the compound was excited by a 235 nm excitation. Graphical Abstract  The preparation, X-ray structure and luminescent property are presented for a new lanthanide metal-organic coordination polymer Yb3(BDC)4.5(DMF)2(H2O)3 · (DMF)2.   相似文献   

6.

Abstract  

The low temperature crystal structure of the complex, Cr(urea)4(H2O)2·3NO3 (1), displays intriguing pseudosymmetry that complicates the structure determination. 1 crystallises in the centrosymmetric monoclinic space group P21/c with Z = 8 and Z′ = 2; a = 18.3338(4) ?, b = 16.5472(4) ?, c = 13.9252(3) ? and β = 106.3260(10)°, V = 4054.19(16) ?3. The two symmetry independent [Cr(urea)4(H2O)2]3+ ions in the asymmetric unit both feature coordinated urea (O=C(NH2)2) and lie on general positions. A further six independent nitrate anions complete the structure. The unit cell is primitive but the two Cr3+ ions are related by a pseudo translation of ?, ?, 0. The deviation from a truly C-centred cell is clear from an examination of geometry of the urea ligands and the hydrogen bonds which they form. The identification of the space group in this case is described and methods for quantifying the degree of deviation from a C-centred cell discussed.  相似文献   

7.

Abstract  

New diphosphates AErP2O7, A = Rb (1), Cs (2), and HEuP2O7·3H2O (3) have been prepared via soft chemistry route from evaporation of aqueous solution. Their crystal structures have been solved by single crystal diffraction data. The compounds (1) and (2) crystallize in the monoclinic space group P21/c with the following unit cell dimensions: (1) a = 7.7248(4) ?, b = 10.9342(6) ?, c = 8.6716(3) ?, β = 105.434(4)° and Z = 4; (2) a = 7.9192(4) ?, b = 10.8606(4) ?, c = 8.7684(5) ?, β = 104.317(5)° and Z = 4. Compound (3) crystallises in the triclinic space group P − 1, with the unit cell parameters: a = 6.4036(5) ?, b = 6.8753(6) ?, c = 9.7964(8) ?, α = 81.706(7)°, β = 80.218(7)°, γ = 88.381(7)°. Crystal structure of (1) and (2) consists of 3D open framework built from [ErO6] octahedra sharing corners with [P2O7] units, leading to the formation of channels running along c direction in which A+ [A = Rb(1), Cs(2)] ions are located. The compound (3), on the other hand, exhibits a lamellar structure, in which edge-sharing polyhedra of eightfold coordinated europium form chains along [010]. These chains are joined in turn to each others using diphosphates bridges. A network of O–H···O hydrogen bonds reinforces the cohesion of the structure of (3). The diphosphate groups in (1), (2) and (3) adopts an eclipsed configuration. IR and Raman spectra of the three new phosphates show usual signals related to the P2O7 diphosphate group and the water molecule. TG and DTA studies were carried out on crystals of (3). The data are correlated to the crystal structures ones.  相似文献   

8.

Abstract  

Reaction of Ph2SnCl2 with 1,3-bis(3,5-dimethylpyrazol-1-yl)-2-propanol (L) in a 1:1 ratio yields L(SnPh2Cl2)2 adduct, which partly hydrolyzes to the title complex (C25H31Cl3N4OSn, Mr = 628.58) during crystal growing in the air. The title complex is of monoclinic, space group P21/n with a = 9.0338(9), b = 17.890(1), c = 17.340(1) ?, β = 95.533(1)o, V = 2798.9(5) ?3, Z = 4, Dc = 1.492 Mg/m3, λ(Mo) = 0.71073 ?, μ = 1.224 mm−1, F(000) = 1272, R = 0.023, wR = 0.054 for 4212 observed reflections with I ≥ (I). The crystal structure indicates that there is no direct interaction between the pyrazolyl ligand and the tin atom, but this complex forms a supramolecular structure through weak intermolecular C–H⋯Cl and O–H⋯Cl hydrogen bonds.  相似文献   

9.
The compound [UO2(NO3)2(H2O)2] · 2C12H18O was synthesized and studied by IR spectroscopy and X-ray diffraction. The structure consists of the neutral island groups [UO2(NO3)2(H2O)2], which belong to the crystal-chemical group AB 01 2 M 1 2 (A = UO2 2+, B 01 = NO3, M 1 = H2O) of uranyl complexes, and 1-adamantyl methyl ketone molecules. The characteristic features of the association of the complexes [UO2(NO3)2(H2O)2] and 1-adamantyl methyl ketone molecules in the crystal structure via hydrogen bonds are considered with the use of Voronoi-Dirichlet polyhedra.  相似文献   

10.
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   

11.

Abstract  

Two lead coordination compounds, Pb(PYTAC)2 (1), and Pb(PYTAC)2(NO3) (2), were grown as single crystals via hydrothermal synthesis (PYTAC = 2-(4-pyridyl) thiazole-4-carboxylate). Both compounds have been identified via single crystal X-ray diffraction. Coordination polymer 1 crystallizes in a triclinic space group P-1 (a = 5.5097(4) ?, b = 7.2822(5) ?, c = 11.3134(8) ?, α = 103.5580(10)°, β = 99.4330(10)°, γ = 97.1050(10)°), and forms 2-D layers parallel to the crystallographic (ac) plane. Coordination polymer 2 crystallizes in a triclinic space group P-1 (a = 9.8102(5) ?, b = 10.5972(6) ?, c = 14.8076(8) ?, α = 91.9350(10)°, β = 100.8050(10)°, γ = 103.1350(10)°), and forms an infinite 1-D chains along the a axis.  相似文献   

12.

Abstract  

The novel supramolecular networks based on Keggin-type polyoxoanion, formulated (Hpy)3[PMo12O40]·2(py) has been synthesized hydrothermally and determined by X-ray diffraction. The compound crystallize in Monoclinic, system with space groups and cell parameters, P2 1 /n, a = 10.9370(2) ?, b = 19.586(3) ?, c = 12.5500(2) ?, β = 98.618(2)°, V = 2657.8(6) ?3. Organic fragments and Keggin anions are connected via N–H···N, N–H···O contacts to form interesting 1D zigzag chain. The molecule is stabilized in solid state by electrostatic forces and intermolecular hydrogen-bonding interactions to give the confirmation of guest [PMo12O40]3− inserting in organic host.  相似文献   

13.
Abstract The cyclotriphosphate salt, ErNa3(P3O9)2 · 9H2O, has been characterized by single-crystal X-ray diffraction [hexagonal, space group , with unit cell parameters of a = b = 30.8451(14), c = 12.8063(8) ?; Z = 18]. The structure consists of alternating layers of [P3O9]3− groups, ErO8 dodecahedra, Na(1)O6 and Na(2)O7 polyhedra linked together by water molecules. The P3O9 rings are grouped along the c-axis in a P3O9–ErO8 arrangement thereby producing broad, hexagonal channels of diameter of 6.65 ? with a side dimension of 3.907 ?. The absence of coincidences for the majority of the IR and Raman bands observed for the cyclotriphosphate salt is in accord with the centrosymmetric structure of the material. The vibrational spectra have been interpreted on the basis of factor group effects. Graphical abstract We report the crystal structure and vibrational spectra of erbium trisodium bis(cyclotriphosphate)nanohydrate salt ErNa 3 (P 3 O 9 ) 2 · 9H 2 O H. Assaaoudi, M. Ijjaali, A. Ennaciri, I. S. Butler* and J. A. Kozinski Crystal structure and vibrational spectra of erbium trisodium bis(cyclotriphosphate) nonahydrate,ErNa3(P3O9)2 · 9H2O. Projection of the coordination polyhedra of ErNa3(P3O9)2 · 9H2O down the c axis  相似文献   

14.
Aquanitrilotris(methylenephosphonato)dirubidium is a 3D coordination polymer with a layer structure. Space group \(P\bar 1\), Z = 2; a = 8.0380(3) Å, b = 9.0522(4) Å, and c = 10.7837(4) Å; α = 113.252(4)°, β = 105.391(3)°, and γ = 96.182(3)°. Rb atoms populate two symmetrically inequivalent positions with c.n. = 8 and 10; significant difference in O–Rb–O angles in the coordination polyhedra is indicative of the ionic type of Rb–O bonds. In the crystal packing, molecules are connected by not only coordination bonds but hydrogen bonds as well.  相似文献   

15.

Abstract  

Water-soluble derivative of formononetin, [Na(H2O)1.5][Na(H2O)3.5] X2·2H2O(X = 4′-methoxy-7-hydroxyisoflavone-3′-sulfonate) was synthesized by sulfonation reaction. It was characterized by IR, 1H NMR and single-crystal X-ray diffraction analysis. Single-crystal X-ray diffraction analysis showed that the title compound crystallized in a triclinic space group P-1 with cell parameters a = 6.9642(15) ?, b = 13.343(3) ?, c = 20.634(5) ?, α = 107.115(3)˚, β = 93.121(4)˚, γ = 91.911(3)˚, V = 1827.3(7) ?−3, D c  = 1.575 Mg m 3, Z = 2. There are two conformers of 4′-methoxy-7-hydroxyisoflavone-3′-sulfonate anions, two kinds of sodium cations, five coordinated water molecules and two lattice water molecules in the crystal structure. The sodium atoms coordinated with the oxygen atoms from water molecules, hydroxyl groups and sulfo-groups to form a Na–O coordinated network. Aromatic π···π stacking interactions and hydrogen bonding existed in the crystal structure of title compound, which together with coordinated interactions and electrostatic interactions between sodium cations and anions sulfonates C16H10O4SO3 lead to the moieties into a three-dimensional network.  相似文献   

16.

Abstract  

The compound [Ni(RPOEt)2(C2H5OH)2](ClO4)2 (1) [RPOEt = bis{(diphenylphosphinyl)methyl}ethyl phosphinate] has been prepared in the form of single crystals and characterized by elemental and thermal analyses, IR spectroscopy and by a single crystal X-ray diffraction study. The complex crystallizes in the triclinic P[`1] P\bar{1} space group with a = 9.8773(5), b = 13.741(1), c = 14.287(1) ?, α = 64.313(9), β = 70.280(5), γ = 89.973(7)o, V = 1620.5(2) ?3, and Z = 1. The nickel(II) atom in 1, situated at the centre of symmetry, is coordinated by four oxygen atoms from two RPOEt ligands and two oxygen atoms from two ethanol molecules in a slightly distorted octahedral environment. The third phosphoryl-oxygen atom from the phosphinate ligand is hydrogen bonded to the oxygen atom of the ethanol molecule coordinated to nickel(II). The complex [Ni(RPOEt)2(C2H5OH)2]2+ cations are linked by the C–H···O hydrogen bonds into one-dimensional chains and by the composite π···π and C–H···π phenyl interactions into a final three-dimensional structure.  相似文献   

17.

Abstract  

A cyanido-bridged Cu(II)–Ag(I) bimetallic complex, [Cu(Imidazole)4{Ag(CN)2}2] has been prepared and structurally characterized. The compound crystallizes in the orthorhombic space group Pmna. The crystal structure of the complex consists of trinuclear molecules made up of one [Cu(Imidazole)4]+2 and two [Ag(CN)2] units. The trinuclear molecules are interlinked to each other through N–H–N and C–H–N hydrogen bonds. The Cu(II) ions are located on mirrors and assume distorted octahedral geometry with the basal plane consisting of four imidazole N-atoms.  相似文献   

18.
The reaction of 2,6-dimethylpyridine with SbCl3 and HCl affords the title compound, the structure of which is ascertained by X-ray diffraction. The unit cell consists of one bridged Sb2Cl82− anion and two 2,6-dimethylpyridinium cations. The trivalent antimony ion is bonded not only directly to chlorine anions, but also is coordinated with chlorine anions by secondary bonds. In the crystal, there exists infinite coordinated chains of [Sb2Cl8] n 2n anions running along the a axis, which link 2,6-dimethylpyridinium cations by N-H…Cl hydrogen bonds.  相似文献   

19.
The compound Rb2[(UO2)2(CrO4)3(H2O)2] · 4H2O was studied by X-ray diffraction. The crystals are monoclinic, a = 10.695(2) Å, b = 14.684(3) Å, c = 14.125(3) Å, β = 108.396(4)°, sp. gr. P21/c, Z = 4, V = 2104.9(7) Å3, and R = 0.0491. The main structural units are layers consisting of [(UO2)2(CrO4)3(H2O)2]2? anions belonging to the crystal-chemical group A 2 T 2 3 B 2M 2 1 (A = UL 2 2+ , T 3 and B 2 are CrO 4 2? , and M 1 is H2O) of uranyl complexes. The uranium-containing layered groups are held together by electrostatic interactions with rubidium cations, as well as by hydrogen bonds with the participation of inner- and outer-sphere water molecules.  相似文献   

20.
A new diphosphopentamolybdate(VI) K5[HP2Mo5O23] · 10H2O has been prepared employing solution method and characterized by single crystal X-ray diffraction, energy dispersive analysis, infrared spectroscopy, thermal stability analysis, cyclic voltammetry analysis, and ultraviolet visible spectroscopy. The compound crystallizes in the orthorhombic sp. gr. Pcab: a = 15.9661(10) Å, b = 19.0832(10) Å, c = 20.0970(9) Å, V = 6123.27(10) Å3, Z = 8. The crystal structure contains the polyanion units [HP2Mo5O23]5– around the potassium cations and lattice water. The [HP2Mo5O23]5– subunits are connected together through K?O?Mo bridges and hydrogen bonds. The crystal shape morphology was simulated using the Bravais–Friedel–Donnay–Harker model.  相似文献   

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