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1.
The synthesis and X-ray diffraction study of compound Rb2[(UO2)2(C2O4)3], which crystallizes in the monoclinic crystal system, are performed. The unit cell parameters are as follows: a = 7.9996(6) Å, b = 8.8259(8) Å, c = 11.3220(7) Å, β = 105.394(2)°, and V = 770.7(1) Å3; space group P21/n, Z = 2, and R 1 = 0.0271. [(UO2)2(C2O4)3]2? layers belonging to the AK 0.5 02 T 11 crystal chemical group of uranyl complexes (A = UO 2 2+ , K 02 = C2O 4 2? , and T 11 = C2O 4 2? ) are uranium-containing structural units of the crystals. The layers are connected with outer-sphere rubidium cations by electrostatic interactions.  相似文献   

2.
A new radical cation salt based on 4,5-(1,4-dioxanediyl-2,3-dithio)-4′,5′-ethylenedithiotetrathiafulvalene (DOET) with the photochromic anion [Fe(CN)5NO]2?, namely, (DOET)4[Fe(CN)5 NO]1.25(C6H5Cl)0.75, is synthesized. Single crystals of this salt are studied using X-ray diffraction [a = 10.398(2) Å, b = 11.168(2) Å, c = 18.499(4) Å, α = 103.14(3)°, β = 92.80(3)°, γ = 106.02(3)°, V = 1996.3(7) Å3, space group \(P\bar 1\), and Z = 1]. In the structure, radical cation layers alternate with anion layers along the c axis. The centrosymmetric dimers are formed by DOET radical cations in the donor layer with packing of the β type. Like the vast majority of DOET-based salts, the new salt possesses semiconductor properties.  相似文献   

3.
Compound [UO2(C5H12N2O)5](ClO4)2 is synthesized and characterized by thermogravimetry, IR spectroscopy, and X-ray diffraction. The compound crystallizes in the monoclinic crystal system; a = 15.2985(9) Å, b = 26.9676(15) Å, c = 20.6962(11) Å, β = 100.697(1)°, space group P21/c, Z = 8, and R = 0.0445. Discrete [UO2(C5H12N2O)5]2+ groups belonging to the AM 5 1 crystal chemical group of uranyl complexes (A = UO 2 2+ and M 1=C5H12N2O) are uranium-containing structural units of the crystals.  相似文献   

4.
The [Co2 L 4(C4H9COO)4(H2O)] coordination compound of cobalt(II) valerate with nicotinamide (L) is synthesized and studied by IR spectroscopy. The crystal structure of the synthesized compound is determined. The crystals are triclinic, and the unit cell parameters are as follows: a = 10.2759(10) Å, b = 16.3858(10) Å, c = 16.4262(10) Å, α = 100.538(10)°, β = 101.199(10)°, γ = 90.813 (10)°, Z = 2, and space group P \(\bar 1\). The structural units of the crystal are dimeric molecular complexes in which pairs of cobalt atoms are linked by triple bridges formed by oxygen atoms of two bidentately coordinated valerate anions and a water molecule. The octahedral coordination of each cobalt atom is complemented by the pyridine nitrogen atoms of two nicotinamide ligands and the oxygen atom of the monodentate valerate group. The hydrocarbon chains of the valerate anions are disordered over two or three positions each.  相似文献   

5.
The crystal structure of monoclinic La3SbZn3Ge2O14 crystals from the langasite family is determined by X-ray diffraction analysis [a = 5.202(1) Å, b = 8.312(1) Å, c = 14.394(2) Å, β = 90.02(1)°, sp. gr. A2, Z = 2, and R/R w = (5.2/4.6)%]. The structure is a derivative of the Ca3Ga2Ge4O14-type structure (a = 8.069 Å, c = 4.967 Å, sp. gr. P321, Z = 1). The crystal studied is a polysynthetic twin with the twin index n = 2, whose monoclinic components are related by pseudomerohedry by a threefold rotation axis of the supergroup P321.  相似文献   

6.
A new compound (Rb0.50Ba0.25)[UO2(CH3COO)3] is synthesized and its crystal structure is studied by X-ray diffraction. The compound crystallizes in the form of yellow plates belonging to the cubic crystal system. The unit cell parameter a = 17.0367(1) Å, V = 4944.89(5) Å3, space group I \(\bar 4\)3d, Z = 16, and R = 0.0182. The coordination polyhedron of the uranium atom is a hexagonal bipyramid with oxygen atoms of three acetate groups and the uranyl group in the vertices. The crystal chemical formula of the uranium-containing group is AB 3 01 (A = UO 2 2+ , B 01 = CH3COO?). The oxygen atoms of the acetate groups that enter the coordination polyhedron of uranium are bound to barium and rubidium atoms.  相似文献   

7.
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   

8.
An accurate structure analysis of a Ba3TaGa3Si2O14 single crystal from langasite family was performed using four X-ray diffraction data sets collected on a diffractometer equipped with a CCD area detector (sp. gr. P321, Z = 1, sinθ/λ ≤ 1.35 Å–1; at 295 K a = 8.516(1) Å, c = 5.1910(6) Å, R/wR = 0.58/0.56%, Δρmin/Δρmax =–0.73/0.42 e/Å3, 4414 independent reflections; at 106 K a = 8.5109(9) Å, c = 5.1861(9) Å, R/wR = 0.75/0.86%, Δρmin/Δρmax =–0.81/1.06 e/Å3, 4382 reflections). The distinguishing feature of the Ba3TaGa3Si2O14 structure is a strong disorder of the Ga atom at the 3f site. Structural transformations in the series of Сa3TaGa3Si2O14–Sr3TaGa3Si2O14–Ba3TaGa3Si2O14–Ba3TaFe3Si2O14 crystals were analyzed.  相似文献   

9.
A new compound of composition Bi2.53Li0.29Nb2O9 was synthesized in the course of the search for new materials with high ionic conductivity. Its crystal structure was determined from the neutron diffraction data. The new compound Bi2.53Li0.29Nb2O9 is crystallized in the orthorhombic system, sp. gr. Cmc21, and unit-cell parameters a = 24.849(1) Å, b = 5.4536(3) Å, and c = 5.4619(2) Å at T = 290 K (a = 24.843(2) Å, b = 5.4456(5) Å, and c = 5.4546(5) Å at T = 10 K). Within the temperature range 10–870 K, no structural phase transitions were revealed. The atomic coordinates and the thermal factors in the isotropic approximation were refined by the Rietveld method at 290 and 10 K. The data obtained were analyzed based on the calculated local balance of bond strengths.  相似文献   

10.
The mixed tris-cyclopentadienyl tetrahydrofuranato samarium complex bis-(cyclopentadienyl) methylcyclopentadienyl tetrahydrofuranato samarium (I) was synthesized by reaction of (C5H5)2SmCl with methyl cyclopentadienyl sodium in THF. [(C5H5)2(C5H4CH3)(C4H8O)Sm] (I) was characterized by elemental analyses—IR spectra and MS spectra. The structure of [(C5H5)2(C5H4CH3)(C4H8O)Sm] (I), which has two slightly different independent molecules per asymmetric unit, has been elucidated through complete X-ray analysis. The crystals are monoclinic, with a = 12.791(3) Å, b = 10.467(2) Å, c = 26.108(5) Å, β = 98.22(2)°, and space group Cc, R = 0.0381 for 2103 observed-reflection with I ≥ 3σ(I).  相似文献   

11.
A solid solution of the GaIn3Se6 (2Ga0.5In1.5Se3) composition with a hexagonal lattice (a = 7.051(3) Å, c = 19.148(2) Å, sp. gr. P61, z = 6, V = 824.4332(4) Å3, ρ = 5.379(2) g/cm3) has been synthesized as a result of alloying Ga, In, and Se elements with a metal ratio of 1: 3. It was established that six out of nine In atoms in the lattice are located in a trigonal bipyramid, while the other three In atoms and three Ga atoms have a tetrahedral coordination.  相似文献   

12.
CsFe(MoO4)2 single crystals have been grown by solution-melt crystallization with a charge-to-solvent ratio of 1: 3 (with Cs2Mo3O10 used as a solvent). The crystal structure of this compound has been refined by X-ray diffraction (X8 APEX automatic diffractometer, MoK α radiation, 356 F(hkl), R = 0.0178). The trigonal unit cell has the following parameters: a = b = 5.6051(2) Å, c = 8.0118(4) Å, V = 217.985(15) Å3, Z = 1, ρcalc = 3.875 g/cm3, and sp. gr. P \(\bar 3\) m1. The structure is composed of alternating layers of FeO6 octahedra (with MoO4 tetrahedra attached by sharing vertices) and CsO12 icosahedra.  相似文献   

13.
The absolute structure of La3Ga5SiO14 piezoelectric crystals (a = 8.1746(6) Å, c = 5.1022(4) Å, space group P321, Z = 1) with the positive sense of rotation of the plane of polarization is refined using X-ray diffraction analysis (R = 1.37%, R w = 1.71%, 2413 unique reflections, max sinθ/λ = 1.15 Å?1). The contributions from the anharmonicity of thermal vibrations of lanthanum atoms are calculated with the use of the components of the third-and fourth-rank tensors. It is demonstrated that these contributions can have a significant effect.  相似文献   

14.
TlMnS2 and TlMnSe2 crystals have been synthesized by the method of solid-state reaction from chemical elements weighted in the stoichiometric ratio. X-ray, magnetic, and electric studies have been performed. It is established that the TlMnS2 compound crystallizes in the tetragonal structure with the unit-cell parameters a = 7.74 Å, c = 30.60 Å, Z = 20, and ρx = 6.40 g/cm3; TlMnSe2 crystallizes in the hexagonal structure with the unit-cell parameters a = 6.53 Å, c = 23.96 Å, Z = 8, and ρx = 6.71 g/cm3. TlMnS2 and TlMnSe2 are semiconductors and exhibit an antiferromagnetic character of exchange interaction.  相似文献   

15.
Bis(acetylacetonato)oxovanadium C10H14O5V (I) and (S)-[2-(N-salicylidene)aminopropionate]oxovanadium monohydrate C10H9NO5V (II) are synthesized. The crystal structures of compounds I and II are determined using single-crystal X-ray diffraction. Crystals of compound I are triclinic, a = 7.4997(19) Å, b = 8.2015(15) Å, c = 11.339(3) Å, α = 91.37(2)°, β = 110.36(2)°, γ = 113.33(2)°, Z = 2, and space group \(P\bar 1\). Crystals of compound II are monoclinic, a = 8.5106(16) Å, b = 7.373(2) Å, c = 9.1941(16) Å, β = 101.88(1)°, Z = 2, and space group P21. The structures of compounds I and II are solved by direct methods and refined to R1 = 0.0382 and 0.0386, respectively. The oxovanadium complexes synthesized are investigated by vibrational spectroscopy.  相似文献   

16.
A solid solution of the Cu1.95Ni0.05S composition has been synthesized for the first time due to the partial replacement of Cu with Ni atoms in Cu2S. The polymorphic transformations in the polycrystalline samples in the temperature range of 300–1400 K have been investigated by X-ray diffraction and differential thermal analysis. It is established that, at room temperature, the synthesized Cu1.95Ni0.05S samples have an orthorhombic lattice with unit-cell parameters a = 26.50 Å, b = 15.39 Å, and c = 13.85 Å (sp. gr. Abm2). Heating to T = 379 ± 2 K leads to its transformation into a hexagonal lattice with parameters a = 3.960 Å and c = 6.78 Å (sp. gr. P63/mmc). At 750 ± 2 K, the hexagonal modification is transformed into a cubic one with period a = 5.788 Å (sp. gr. Fm\(\bar 3\)m). The phase transition in this crystal is enantiotropic.  相似文献   

17.
Herein we report the crystal structure of trans-PdCl2(PPh2C12H7S3)2, 1, in a different morphology than has previously been reported [Stott et al. (Dalton Trans (4):652–653, 2005]. This structure crystallizes in a P-1 space group with a = 9.4249(19) Å, b = 11.540(2) Å, c = 12.559(3) Å, α = 79.07(3)°, β = 78.04(3)°, γ = 69.44(3)°, Z = 1. The earlier structure possessed a P21/n space group. Additionally the terthienyl moieties of 1 demonstrate the anti orientation exclusively while the P21/n space group structure has some syn and even syn/anti mixed geometries included.  相似文献   

18.
When studying the phase formation in the CaO-Li2O-B2O3-H2O system, a new Ca,Li pentaborate was synthesized under hydrothermal conditions. The structure of a new compound with the crystallochemical formula CaLi4[B5O8(OH)2]2 (sp. gr. Pb2n, a = 8.807(7), b = 9.372(7), c = 8.265(6) Å, V = 682.2(9) Å3, Z = 2, dcalcd = 2.43 g/cm3, automated SYNTEX-\(P\bar 1\) diffractometer, 2690 reflections, 2θ/θ scan, λMo) is refined up to Rhkl = 0.0557 in the anisotropic approximation of atomic thermal vibrations with allowance for the localized H atoms. The structure of the Ca,Li pentaborate is formed by (010) open boron—oxygen layers formed by two independent [B5O8(OH)2]3? pentagroups, with each of them being formed by three B tetrahedra and two B triangles. The structure framework consists of the above boron—oxygen layers bound by isolated Li tetrahedra. The Ca cations are localized in the centers of eight-vertex polyhedra located in the [001] channels of the Li,B,O framework. Comparative crystallochemical analysis of the new Ca,Li pentaborate and Li pentaborate of the composition Li3[B5O8(OH)2]-II showed that the anionic matrices of both compounds are completely identical, whereas some of the cationic positions are different.  相似文献   

19.
The crystal structure of the high-temperature β modification of synthetic orthophosphate KU2(PO4)3 was refined from powder X-ray diffraction data by the Rietveld method: sp. gr. \(R\bar 3c\), the unit-cell parameters a= 9.113(1) Å and c= 24.997(1) Å. The isotropic refinement converged to R wp = 6.15, R B = 2.14, R F = 3.52, and S = 0.42. It was confirmed that β-KU2(PO4)3 belongs to the structure type of sodium zirconium phosphate containing an actinide atom in a sixfold (octahedral) coordination formed by oxygen atoms, which is unusual for orthophosphates. The principal interatomic distances and bond angles in the structure are reported.  相似文献   

20.
The crystal structure of two borophosphates, Rb(Al,Fe)[BP2O8(OH)] (a = 9.381(6), b = 8.398(5), c = 9.579(6) Å, β = 102.605(10)°, sp. gr. P21/c) and K(Fe,Al)[BP2O8(OH)] (a = 5.139(2), b = 8.065(4), c = 8.290(4)Å, α = 86.841(8)°, β = 80.346(8)°, γ = 86.622(8)°, sp. gr. P \(\bar 1\)), obtained by hydrothermal synthesis in the AlCl3: FeCl3: K3PO4(Rb3PO4): B2O3: H2O system has been established using X-ray diffraction (Bruker Smart diffractometer, T = 100 K). Hydrogen atoms are located and their coordinates and thermal parameters are refined. It is shown that the polymorphism of the [BP2O8(OH)]4? borophosphate anion has a morphotropic nature and is related to the substitutions both in the cationic part of the structure and in the octahedral position of the anionic mixed framework. The synthesis of new isotypic triclinic compounds under hydrothermal conditions is predicted.  相似文献   

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