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1.
The crystal structure of a newly synthesized compound Na2Ba2[B10O17(OH)2] has been determined (Syntex \(P\bar 1\) diffractometer, MoKα radiation, 1784 crystallographically nonequivalent reflections, anisotropic approximation, R = 1.7%). The parameters of the monoclinic unit cell are a = 11.455(7), b = 6.675(4), c = 9.360(7) Å, β = 93.68(5)°, Z = 2, sp. gr. C2. The structure consists of double pseudohexagonal layers built by BO4-tetrahedra and BO3-triangles forming three-membered rings of two mutually orthogonal orientations. The neighboring layers along the [001] direction are bound by Na-polyhedra and hydrogen bonds with participation of OH groups. The interlayer tunnels along the [100] direction are filled with columns of Ba-polyhedra. The crystallochemical characteristics of a number of synthetic Ba-borates (to which the structure of new decaborate is related) are considered in terms of borate building blocks singled out in the structure.  相似文献   

2.
A new centrosymmetric modification of Pb-hilgardite Pb2[B5O9](OH) · 0.5H2O is synthesized hydrothermally under conditions close to natural. This modification is intermediate between the centrosymmetric monoclinic phase studied earlier and the polar orthorhombic phase. The occupancies of the framework voids with water molecules, OH-groups, and halogen atoms are considered for all the known varieties of hilgardite. The correlation between the conditions of hilgardite formation and types of structure is established.  相似文献   

3.
The crystal structure of Rb2Mn3(H2O)2[P2O7]2, a new phase obtained in the form of single crystals under hydrothermal conditions in the MnCl2–Rb3PO4–H2O system, is determined by X-ray diffraction (Xcalibur-S-CCD diffractometer, R = 0.0270): a = 9.374(2), b = 8.367(2), c = 9.437(2) Å, ß = 99.12(2)°, space group P21/c, Z = 2, Dx = 3.27 g/cm3. A correlation between the unit-cell parameters and the size of cations forming the crystal structures of isostructural A2M3(H2O)2[P2O7]2 diphosphates (A = K, NH4, Rb, or Na; M = Mn, Fe, Co, or Ni) is revealed. It is shown that, due to the topological similarity, the structures of diphosphates and orthophosphates of the farringtonite structural type can undergo mutual transformations.  相似文献   

4.
The mixed-valence compound [Li(THF)4]Cu2Br4 was synthesized in a redox reaction from 1,4-dihydroxynaphthalene, CuBr2 and LiNtBuSiMe3 in THF. X-ray quality crystals of [Li(THF)4]Cu2Br4 (monoclinic, P21/c) are obtained from the mother liquor at ambient temperature. In the solid state, infinite chains of anionic [Cu2Br4] units are established. These chains are separated by [Li(THF)4]+ cations.  相似文献   

5.
The crystal structure of synthetic manganese sodium borophosphate hydrate Na(H2O)[Mn(H2O)2(BP2O8)] was refined based on X-ray diffraction data. The compound was prepared by soft hydrothermal synthesis in the MnCl2-Na3PO4-B2O3-H2O system. The unit-cell parameters are a= 9.602(1) Å, c= 16.037(3) Å, sp. gr. P6522, Z= 6, D x = 2.57 g/cm3. The water molecules were found to be statistically distributed in the channels of the mixed anionic paraframework consisting of (BO4) and (PO4) tetrahedra and [MnO4(H2O)2] octahedra. The hydrogen atoms of the water molecules coordinated to the Mn2+ cations were located and their positional and thermal parameters were refined. The crystal-chemical features of borophosphates of the general formula A x M(H2O)2(BP2O8)(H2O) are considered.  相似文献   

6.
The crystal structure of the new compound Rb2[Ti(VO2)3(PO4)3] obtained by hydrothermal synthesis in the RbCl-TiPO4-V2O5-B2O3-H2O system (a = 13.604(2) Å, c = 9.386(2) Å, sp. gr. P6cc, Z = 4, ρcalcd = 3.32 g/cm3) has been studied by X-ray diffraction (Xcalibur-S-CCD diffractometer, R = 0.038). It is shown that the isotypism of Rb2[Ti(VO2)3(PO4)3] and Cs2[Ti(VO2)3(PO4)3] is caused by the flexibility of a mixed anionic framework composed of phosphorus tetrahedra, vanadium five-vertex polyhedra, and titanium octahedra (bases of the crystal structures of these compounds). The topological correlations between the structures of titanium-vanadyl phosphates and benitoite and beryl silicates are analyzed.  相似文献   

7.
The crystal structure of the (Al,V)4(P4O12)3 solid solution, obtained in the single-crystal form by hydrothermal synthesis in the Al(OH)3-VO2-NaCl-H3PO4-H2O system, has been solved by X-ray diffraction analysis (Xcalibur-S-CCD diffractometer, R = 0.0257): a = 13.7477(2) Å, sp. gr. I \(\bar 4\)3d, Z = 4, and ρcalcd = 2.736 g/cm3. It is shown that the crystal structure of the parent cubic Al4(P4O12)3 modification can formally be considered an archetype for the formation of double isosymmetric tetraphosphates on its basis.  相似文献   

8.
Compound Pb3[IO3]2Cl4 (space group C12/c1), representing a new iodate-chloride class of compounds, is synthesized under hydrothermal conditions. Only two minerals, schwartzembergite Pb3[IO3]Cl2O(OH) and seeligerite Pb3[IO3]Cl3O, the structures of which are unknown, are close in composition to this compound. In the iodate-chloride studied, the pentavalent iodine atom has an umbrella-like coordination, which is typical of iodates and consists of three O atoms at short distances and the fourth O atom at a longer distance. [IO4]3− tetrahedra share edges to form pairs. Lead ions form layers parallel to the ab plane. Along the c axis, these layers alternate with layers of iodate groups. Pb atoms are coordinated by O atoms of iodate groups and Cl atoms. The coordination sphere of the Pb(1) atom contains a free sector which is directed to more distant halogen atoms and possibly accommodates the lone electron pair.  相似文献   

9.
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   

10.
The structural features responsible for the high nonlinear optical activity of crystals of the hilgardite-like anhydrous bromo-borate Pb2[B5O9]Br (space group Pnn2) are analyzed with the use of data obtained from two (precision and conventional) single-crystal X-ray diffraction experiments. The electron-density peaks associated with the stereochemically active lone electron pair are located in free space at two equally probable positions in the vicinity of the Pb(2) atom on the side of the two most distant atoms, Br(1) and Br(2). The stereochemical activity of two nonequivalent lead atoms in the crystal structure increases upon changing over from the Pb(1) atom to the Pb(2) atom. This is in agreement with the behavior of the lone electron pairs in the hilgardite-like hydrated borate Na0.5Pb2[B5O9](OH)1.5 · 0.5H2O and another nonlinear optical borate, namely, Pb2[B4O5(OH)4](OH)2 · H2O, which is related to the compound BiB3O6. The most pronounced nonlinear optical properties of the lead bromo-borate Pb2[B5O9]Br as compared to other orthorhombic hilgardites and lead borates are associated with the presence of highly polarized Pb-Br bonds. In this case, the electron density of the lone electron pair of the Pb(2) atom enhances the polarization effect.  相似文献   

11.
[Cd5(OH)(H2O)3][CH3CO2]9 crystallizes in the triclinic system, with the space group P , a = 10.897(3) Å, b = 11.035(5) Å, c = 16.061(12) Å, = 96.83(7), = 95.31(8), = 118.22(6) and z = 2. Its structure has been determined using 9497 unique single crystal data. The final refinements let the agreement factors R1 and wR2(F2) converge to reach the respective values of 0.0548 and 0.0986. R1 = 0.0338 for the 7264 unique data with I > 2(I). [Cd5(OH)(H2O)3][CH3CO2]9 is a cadmium hydroxide acetate compound with a bi-dimensional structure in which hydrogen bonds insure cohesion between layers stacked along the [1 10] direction. The inorganic network is built up of layers constituted of CdO6 octahedra and CdO7 pentagonal bi-pyramids sharing edge or corner.  相似文献   

12.
The crystal structure of the rhombohedral phase of Fe3B7O13Br was determined and compared with the structures of Fe3B7O13Cl and Fe3B7O13I. The influence of the ionic radii of the halogen atom on the structural features of the crystals of the boracite family is discussed.  相似文献   

13.
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   

14.
The crystal structure of a new compound, namely, Nd2TeMo6O24 · 19H2O, is determined using X-ray diffraction. The crystal has a chain structure and consists of [Nd2TeMo6O24 · 14H2O]n neutral chains aligned parallel to the [010] direction and crystallization water molecules. In a chain, each Nd atom links two heteropoly anions. The Nd3+ environment includes seven water molecules and two oxygen atoms of the two heteropoly anions adjacent in the chain. The polyhedron is a monocapped tetragonal antiprism. In the previously studied complex of similar composition, namely, Nd2TeMo6O24 · 18H2O, the Nd coordination polyhedron has the shape of a tricapped trigonal prism formed by six water molecules and three oxygen atoms of the two heteropoly anions adjacent in the chain.  相似文献   

15.

Abstract  

Single crystals of iron and manganese phosphate Fe6.36Mn0.64(PO3(OH))4(PO4)2 was synthesized by hydrothermal method. The compound crystallizes in the Fe7(PO4)6 structure type and is isotypic with the solid solution \textM7 - \textx \textM\textx ( \textHPO4 )4 ( \textPO4 )2 {\text{M}}_{{7 - {\text{x}}}} {\text{M}}_{\text{x}}^{\prime} \left( {{\text{HPO}}_{4} } \right)_{4} \left( {{\text{PO}}_{4} } \right)_{2} where M is Fe, Co, Mg, Mn. The compound is triclinic, P-1, a = 6.571(5), b = 7.993(3), c = 9.547(2) Ǻ, α = 103.97(1)°, β = 109.29(2)°, γ = 101.57(3)°. The structure is based on a three-dimensional framework of distorted edge-sharing MO6 and MO5 polyhedra, forming infinite chains, which are interlinked by corner-sharing with PO4 tetrahedra. The formula unit is centrosymmetric, with all atoms in general positions except for one Fe atom, which has site symmetry −1.  相似文献   

16.
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   

17.
Abstract  Reaction between p-aminobenzoic acid (HpABA) and Cu(NO3)2 · 2.5H2O in basic MeOH/DMF affords green crystals of the dicopper paddlewheel complex, Cu2(pABA)4(DMF)2 · 2DMF, 1, identified by single crystal X-ray crystallography: triclinic P-1, with a = 10.3728(2) ?, b = 10.617(2) ?, c = 11.128(2) ?, α = 81.705(3)°, β = 79.984(2)°, γ = 65.965(2)° and Z = 2. The crystal structure of 1 reveals that it is the second polymorph of Cu2(pABA)4(DMF)2 · 2DMF and experiments on the stability of 1 indicate that it can be converted to Form I through desolvation followed by exposure to DMF. Graphical Abstract  Crystal structure of a polymorphic discrete dicoppertetracarboxylate is investigated for the conversion between the two forms influenced by hydrogen bonds.   相似文献   

18.
A novel cobalt complex [Co(2,5-PDC)2(H2O)2Co(H2O)4]·4H2O (2,5-PDCH2 = 2,5-pyridinedicarboxylic acid) was synthesized and its crystal structure has been determined by X-ray diffraction. The crystallographic data are: triclinic P−1, a = 7.112(2) ?, b = 8.939(3) ?, c = 9.719(3) ?, α = 91.153(5)°, β = 101.136(5)°, γ = 108.001(4)°, V = 574.4(3) ?3, Z = 1. The compound [Co(2,5-PDC)2(H2O)2Co(H2O)4]·4H2O exhibits a novel one-dimensional network constructed from the interconnection of Co(2,5-PDC)2(H2O)2 and Co(H2O)4, in which two kinds of six-coordinated Co(II) atoms have both octahedral coordination environments. Each 2,5-PDC anion connects two different coordinated cobalt ions alternately in an one-dimensional chain. The zigzag 1D alternating chains are linked by extensive hydrogen bonds to form a three-dimensional (3D) supramolecular structure, in which uncoordinated solvate molecules act as space filling particles. Supplementary data CCDC-264249 contains the supplementary crystallographic data for this paper. Copies of this information may be obtained free of charge from the Director, CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK (fax: t44–1223–336033; e-mail: deposit@ccdc.cam.ac.uk or ) or also available from the author Xiaoqing Wang.  相似文献   

19.
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   

20.
Abstract  A new barium chlorovanadate, Ba5(V2O7)2Cl2, was isolated by a high-temperature (850 °C) reaction employing a CsCl/RbCl flux. The structure was determined by single crystal X-ray diffraction methods. This compound crystallizes in an orthorhombic crystal system, Pmmn (No. 59), with a = 11.558(2) ?, b = 15.164(3) ?, c = 10.023(2) ?, Z = 4 and V = 1756.7(6) ?3. The structure of Ba5(V2O7)2Cl2 was determined by full-matrix, least-squares methods with R 1 = 0.0398, wR 2 = 0.1069 and GOF = 1.048 for all data. This new structure can be described as a composite lattice made up of mixed covalent and ionic moities. The extended framework is orchestrated by stacked [Ba(V2O7)Cl]3− slabs that are interconnected by Ba2+ cations through Ba–O bonds to the [V2O7] units. The Ba2+ and Cl- ions form BN-type “[BaCl]” sheets with pseudo-hexagonal windows that are centered by [V2O7]4− pyrovanadate units. Graphical Abstract  The structure of a new chlorovanadate, Ba5(V2O7)2Cl2, exhibits an interesting BN-type salt lattice that consists of an extended [BaCl] sheet containing pseudo-hexagonal windows that are centered by [V2O7] pyrovanadate units.   相似文献   

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