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1.
Single crystals of the compound Na3(H3O)[UO2(SeO3)2]2 · H2O (I) have been synthesized, and their structure has been investigated using X-ray diffraction. Compound I crystallizes in the triclinic system with the unit cell parameters a = 9.543(6)Å, b = 9.602(7)Å, c = 11.742(8)Å, α = 66.693(16)°, β = 84.10(2)°, γ = 63.686(14)°, space group P \(\bar 1\), Z = 2, and R = 0.0734. The uranium-containing structural units of the crystals are [UO2(SeO3)2]2? chains, which belong to the crystal-chemical group AB 2 B 11 (A = UO 2 2+ , B 2 = SeO 3 2? , B 11 = SeO 3 2? ) of the uranyl complexes. The structures of the compounds containing the [UO2(SeO3)2]2? anionic complexes are compared.  相似文献   

2.
The new potassium–bismuth–nickel oxophosphate obtained by hydrothermal synthesis in the Bi(OH)3–NiCO3–K2CO3–K3PO4 system is studied by X-ray diffraction, IR spectroscopy, and Raman spectroscopy. Parameters of the orthorhombic cell are as follows: a = 13.632(1) Å, b = 19.610(2) Å, and c = 5.4377(3) Å; V = 1452.64(2) Å3; and space group Pnma. The structure is solved and refined to the final discrepancy factor R 1 = 5.76% in the anisotropic approximation of atomic displacements using 3606 reflections with I > 2σ(I). The crystal-chemical formula (Z = 4) is KBi4{Ni2O4(PO4)3}, where the composition of the layer nickel–phosphate polyanion is enclosed in braces. Theoretical calculations show that all exchange spin interactions between Ni2+ ions are antiferromagnetic and very weak (J < 0.1 cm–1) because of the polyatomic character of bridging Ni–O–P–O–Ni and Ni–O–Bi–O–Ni groups. Thus, this compound is expected to be paramagnetic with very weak antiferromagnetic exchange interactions and appreciable energy of zero-field splitting of the spin levels of Ni2+ ions.  相似文献   

3.
A new hybrid vanadium arsenate [VO2(phen)]2(H2AsO4)H3O 1 (phen = 1,10-phenanthroline) was synthesized under hydrothermal reaction conditions and structurally characterized by single-crystal X-ray diffraction, thermogravimetric analysis (TGA), IR and elemental analyses. Crystal data for 1: monoclinic, P21/n, a = 9.175(2) Å, b = 18.638(5) Å, c = 14.482(4) Å, = 102.333(3), V = 2419(1) Å3, Z = 4. Compound 1 is composed of discrete tricyclic (VO2)2(H2AsO4) cluster decorated with two phen ligands. The discrete arsenic–vanadium clusters are extended into three-dimensional supramolecular arrays via – stacking interactions of phen groups.  相似文献   

4.
A new radical cation salt based on bis(ethylenedioxy)tetrathiafulvalene (BEDO) with the planesquare anion Ni(CN) 4 2? is synthesized. The molecular and crystal structures of the radical cation salt are determined, and the conducting properties are investigated. In the structure, the BEDO radical cations have a β″-type packing. It is shown that the temperature dependence of the conductivity of (BEDO)4Ni(CN)4 · 4CH3CN crystals exhibits metallic behavior.  相似文献   

5.
The complex Ho2(2-FC6H4COO)6?4H2O has been synthesized and structurally characterized by single crystal X-ray diffraction methods. The complex crystallizes in the triclinic system with space group P \(\bar 1\), lattice parameters a = 9.293(8) Å, b = 9.845(8) Å, c = 12.703(11) Å, α = 85.470(14)°, β = 87.537(12)°, γ = 62.485(11)°, V = 1027.5(15) Å3, Z = 1, Dcalc = 1.998 Mg/m3. The Ho3+ ion is in distorted monocapped square-antiprism coordination environment and is coordinated by nine oxygen atoms, seven from five 2-FC6H4COO2? groups, two from two water molecules. Two Ho3+ ions are linked together by four bridging carboxylate groups to form a binuclear molecule with inversion center.  相似文献   

6.
A proton transfer compound 2,6-dimethyl piperazine-1,4-diium perchlorate monohydrate was synthesized by slow evaporation at room temperature using 2,6-dimethyl piperazine as template. The asymmetric unit contains one organic dication, two crystal graphically independent perchlorate anions and one water molecule. Each organic entities is engaged in a large number of bifurcated and non-bifurcated N–H···O (O) and C–H···O hydrogen bonds with different species and enhanced the three dimensional supramolecular network. In addition, the diprotonated piperazine ring adopts a chair conformation with the methyl groups occupying equatorial positions.  相似文献   

7.
Crystals of new iodate NaIn[IO3]4 were prepared by the hydrothermal synthesis. The unit cell parameters are a = 7.2672(2) Å, b = 15.2572(6) Å, c = 15.0208(6) Å, β = 101.517(3)°, sp. gr. P21/c. The formula was determined during the structure determination and refinement of a twinned crystal based on a set of reflections from the atomic planes of the major individual. The refinement with anisotropic displacement parameters was performed for both twin components to the final R factor of 0.050. The In and Na atoms are in octahedral coordination formed by oxygen atoms. The oxygen octahedra are arranged into columns by sharing edges, and the columns are connected by isolated umbrella-like [IO3] groups to form layers. The new structure is most similar to the isoformular iodate NaIn[IO3]4, which crystallizes in the same sp. gr. P21/c and is structurally similar, but has a twice smaller unit cell and is characterized by another direction of the monoclinic axis. The structural similarity and difference between the two phases were studied by topologysymmetry analysis. The formation of these phases is related to different combinations of identical one-dimensional infinite chains of octahedra.  相似文献   

8.
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   

9.
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   

10.
The stable metal β″-(DOEO)2HSeO4 · H2O I) based on a new donor compound, 3,4-(1,4-dioxanediyl-2,3-dithio)-3′,4′-ethylenedioxo-2,5,2′,5′-tetrathiafulvalene] (DOEO), is synthesized and structurally characterized for the first time. The synthesis is performed by the electrocrystallization technique (direct current density j = 2 × 10?6 A/cm2). The crystals are triclinic, and the unit cell parameters are as follows: a = 5.495(1) Å, b = 9.715(2) Å, c = 16.878(3) Å, α = 83.52(3)°, β = 82.54(3)°, γ = 73.51(3)°, Z = 1, and space group \(P\bar 1\). The salt has a layered structure. The DOEO1/2+ radical cation layers are aligned parallel to the ab planes. The HSeO 4 ? · H2O solvated anions are located in channels along the a axis and are disordered over two positions near the center of symmetry (1/2 0 0) with a probability of 50%. The conductivity of the salt is equal to 300–400 Ω?1 cm?1 at room temperature and increases upon cooling to the boiling point of liquid helium (4.2 K) by a factor of 100–200 depending on the sample.  相似文献   

11.
Single crystals of the cubic βms-phase of La1.82Bi0.18Mo2O9 have been characterized for the first time by precision X-ray diffraction at 33 K. The structure of a crystal determined at T = 33 K is identical to the structure studied at room temperature. It is confirmed that the La, Mo1, and O1 atoms deviate from their positions on the threefold axis in the high-temperature β-phase; part of lanthanum atoms is substituted by bismuth atoms, which are located on the threefold axis; part of the molybdenum atoms return to the position on the threefold axis.  相似文献   

12.
Crystals of UO2CrO4(C5NH5COO)2(H2O)] · 2H2O are synthesized and their structure is studied by X-ray diffraction. The compound crystallizes in the triclinic crystal system. The unit cell parameters are as follows: a = 7.0834(10) Å, b = 10.6358(14) Å, c = 12.9539(17) Å, α = 75.096(2)°, β = 74.490(2)°, and γ = 80.657(2)°; V = 904.1(2) Å3, space group P \(\bar 1\), Z = 2, and R = 0.026. The structure is built of [UO2CrO4(C5NH5COO)2(H2O)]2 centrosymmetric dimers, which are linked into a framework by a system of hydrogen bonds involving inner-sphere and outer-sphere water molecules. The coordination number of the U(VI) atom is seven, and the coordination polyhedron is a pentagonal bipyramid with the oxygen atoms of the uranyl group, two chromate groups, two molecules of isonicotinic acid, and a water molecule at the vertices. The crystal chemical formula of the [UO2CrO4(C5NH5COO)2(H2O)]2 dimer is represented as AB 2 M 3 1 , where AB 2 M 3 1 , where A = UO 2 2+ , B 2 = CrO 4 2? , and M 1 = = C5NH4COOH and H2O.  相似文献   

13.
Ba3TaFe3Si2O14 single crystals (sp. gr. P321, Z = 1), promising langasite-type multiferroics, have been grown by floating zone melting. An accurate X-ray diffraction study of Ba3TaFe3Si2O14 single crystal has been performed using two datasets, obtained independently for two different orientations of the same sample on a diffractometer equipped with a CCD area detector at 295 K. Structure refinement is performed based on an averaged dataset: a = 8.5355(1) Å, c = 5.2332(1) Å, sp. gr. P321, Z = 1; the R factors of model structure refinement were found to be R/wR = 1.02/1.23% for 4552 independent reflections. Disordering asymmetry is revealed for the magnetic Fe ion in the 3f site and the Ba cation in the 3e site.  相似文献   

14.
The crystal structure of nitrilotris(methylenephosphonato)potassium K[μ6-NH(CH2PO3)3H4]—a three-dimensional coordination polymer—was determined. The potassium atom is coordinated by seven oxygen atoms belonging to the six nearest ligand molecules, resulting in distorted monocapped octahedral coordination geometry. The complex contains the four-membered chelate ring K–O–P–O. The K–O chemical bond is predominantly ionic. Meanwhile, the bonds of the potassium atom with some oxygen atoms have a noticeable covalent component. In addition to coordination bonds, the molecules in the crystal packing are linked by hydrogen bonds.  相似文献   

15.
The structure of the natural mineral calcio-olivine (γ-Ca2SiO4) found in skarn xenoliths in the region of the Lakargi Mountain (North Caucasus, Kabardino-Balkaria, Russia) is refined by the Rietveld method [a = 5.07389(7) Å, b = 11.21128(14) Å, c = 6.75340(9) Å, V = 384.170(5) Å3, Z = 4, ρcalcd = 2.98 g/cm3, space group Pbnm]. The X-ray diffraction pattern of a powdered sample is recorded on a STOE STADI MP diffractometer [λCuK α1; Ge(111) primary monochromator; 6.00° < 2θ < 100.88°; step width, 2.5° in 2θ; number of reflections, 224]. All calculations are performed with the WYRIET (version 3.3) software package. The structural model is refined in the anisotropic approximation to R p = 6.44, R wp = 8.52, R exp = 5.85, R B = 4.98, R F = 6.90, and s = 1.46. It is shown that the sample under investigation is a mixture of several mineral phases, among which calcio-olivine (the natural analogue of the γ-Ca2SiO4 compound) (83%), hillebrandite (13%), and wadalite (4%) are dominant. Only the scale factors and the unit cell parameters are refined for hillebrandite Ca2SiO3(OH)2 [a = 3.63472(16) Å, b = 16.4140(10) Å, c = 11.7914(8) Å, space group Cmc21, Z = 6] and wadalite Ca6Al5Si2O16Cl3 (a = 12.0088 Å, space group, I \(\bar 4\)3d Z = 4). The results of the structure refinement of the main component of the sample confirm that the mineral calcio-olivine is isostructural to the synthetic compound γ-Ca2SiO4. The structure of this compound is formed by the heteropolyhedral framework composed of Ca octahedra joined together into olivine-like ribbons and isolated Si tetrahedra.  相似文献   

16.
The structure of a single crystal of tetraammindioxoosmium(VI) sulfate [OsO2(NH3)4]SO4 · H2O, which is synthesized by the reaction of K2[OsO2(OH)4] with (NH4)2SO4 in an aqueous solution, is investigated using X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system, space group P21/c, a = 13.102(2) Å, b = 6.158(3) Å, c = 11.866(2) Å, β = 98.13(2)°, and Z = 4. The [OsO2(NH3)4]SO4 · H2O compound has an island structure. Two crystallographically independent osmium atoms are situated at the centers of symmetry, and their octahedral coordination includes two oxygen atoms and four nitrogen atoms of the ammonia molecules. In both octahedra, the osmyl group is linear. The Os-O distances in the octahedra are identical within the standard deviations [Os(1)-O, 1.762(2) Å; Os(2)-O, 1.769(2) Å]. The Os-N bond lengths vary from 2.082(3) to 2.101(3) Å. The cationic complexes, SO4 groups, and water molecules are linked via the system of hydrogen bonds. The assignment of the absorption bands in the IR spectrum of the compound synthesized is performed, and its thermal behavior in air is studied.  相似文献   

17.
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   

18.
The structure and electrical and optical properties of β-Ga2O3–In2O3 thin films on sapphire substrates with different orientations have been investigated. The samples have been prepared by annealing of gallium–indium metallic films on sapphire substrates in air at different gallium-to-indium ratios in the initial mixture. The photoconductivity of these structures in the solar-blind ultraviolet spectral region has been examined.  相似文献   

19.

Abstract  

The synthesis and crystal structure are presented for the ethylenediammonium bis iodate tetra iodic acid. An X-ray investigation has shown that this compound crystallizes in a centrosymmetric monoclinic system, space group P21/c with the lattice parameters: a = 7.2536(2) ?, b = 18.5351(5) ?, c = 7.5685(2) ?, β = 107.937(1)°, V = 968.10(3) ?3. The structure was solved from 5281 independent reflections with R 1 = 0.0229 and wR 2 = 0.0428, and refined with 156 parameters. The structure is built up of [(CH2)2(NH3)2]2+ cations connected to the one-dimensional [HIO3]n chains and to the [H2I4O12]2− clusters by a weak N–H···O hydrogen bonds.  相似文献   

20.
Aqua{pentahydrogennitrilotris(methylenephosphonato)}lithium hydrate is a linear coordination polymer. Its crystal structure is described in space group P1, Z = 2; a = 5.5732(2), b = 7.0106(2), and c = 16.9010(5) Å; α = 97.515(2)°, β = 94.551(2)°, and γ = 95.123(2)°. The tetrahedral coordination of the Li atom includes two oxygen atoms of a phosphonate ligand, one oxygen atom of another phosphonate ligand, and a water molecule. Complex formation is accompanied by closing of the eight-membered Li–O–P–C–N–C–P–O chelate ring. Polymeric chains run along the [100] direction. The chains are connected by hydrogen bonds.  相似文献   

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