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1.
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   

2.
Single crystals of (NpO2)2SO4 · 6H2O are obtained, and their structure is determined. The structure is built of NpO 2 + dioxo cations, SO 4 2? anions, and molecules of coordination and crystallization water. The NpO 2 + ions are linked into cationic ribbons stretched along the [001] direction. In the ribbons, neptunoyl ions of one type act as monodentate ligands, whereas neptunoyl ions of the other type coordinate the neighboring neptunoyl groups by two oxygen atoms. The Np(1) and Np(2) atoms have oxygen environments in the shape of a pentagonal bipyramid whose equatorial plane consists of oxygen atoms of the neighboring dioxo cations, sulfate ions, and water molecules. The sulfate ion acts as a bidentate ligand bridging the two neighboring atoms Np(1) and Np(2). Six water molecules are revealed in the structure; one of them is a crystallization water molecule. Hydrogen bonds link cationic ribbons into a three-dimensional network.  相似文献   

3.
The structure of Na,Ca,Zr-silicate lovozerite, Na2CaZr[Si6O12(OH,O)6] · H2O, from the Khibiny alkaline massif (the Kola Peninsula) was refined by single-crystal X-ray diffraction analysis (Syntex $P\bar 1$ diffractometer, λMoK α radiation, 2θ/θ scanning technique). The refinement (R hkl = 0.077, 1531 independent reflections; anisotropic thermal parameters) confirmed the trigonal system proposed for the mineral earlier (sp. gr. R3; a = 10.18(1) Å, c = 13.13(2) Å, Z = 3) and revealed the presence of two additional positions (C and B) statistically occupied by Ca and Na atoms (and partly by Mn) and H2O molecules, respectively.  相似文献   

4.
[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   

5.
The (HAgu)2B6H6 · 2H2O compound was synthesized and its crystal structure was determined [R = 0.0385 for 2018 reflections with I > 2σ(I)]. The structure consists of HAgu + cations, centrosymmetric B6H 6 2? anions, and water molecules. The anions have an almost regular octahedral structure. The bond lengths and angles lie within the following narrow ranges: B-B, 1.715–1.726(2) Å; B-H, 1.08–1.14(2) Å; B-B-B, 59.72°–60.29(9)° and 89.63°–90.20(11)°; and B-B-H, 133.2°–137.0(9)°. The HAgu + cations and water molecules are involved in the O-H?O, N-H?O, and N-N?N hydrogen bonds and participate in numerous (N, O)-H?H-B specific interactions with the B6H 6 2? anions, which results in splitting and high-frequency shift of the band of B-H stretching vibrations in the IR spectrum.  相似文献   

6.
Dicesium Di--sulfatosulphatobisaquothorate(IV), H4O14S3Cs2Th, (M r =821.8) crystallized from water in the monoclinic space groupP21/c (No. 14), witha=6.415(2),b=15.95(1),c=13.078(8) Å,=90.88(4)°,V=1338(14) Å3,Z=4,D x =4.08 g cm–3, MoK (=0.71069 Å),=195.8 cm–1,F(000)=1407.3, room temperature, finalR=0.086 for 1699 unique observed reflexions. Two of the sulfate groups are tridentate (chelating and bridging) and the other is bidentate chelating. As the waters are both coordinated the thorium is 10-coordinate. It shows an unusual 2/4/2/2 geometry.  相似文献   

7.
The structure of [trans-FeCl2(imidazole)4]Cl has been determined as the THF/H2O solvate. The Fe-Cl and Fe-N distances in the cation are shorter than analogous trans-FeCl2(L)4 compounds, concomitant with the decreased ionic radius of Fe3+ versus Fe2+. Crystal data: orthorhombic, Pnma, a = 8.456(2), b = 20.991(4), c = 13.288(3) Å, V = 2358.6(8), andZ = 4.  相似文献   

8.
Crystallography Reports - The growth kinetics of the (001) and (110) faces of K2Co(SO4)2 · 6H2O and K2Ni(SO4)2 · 6H2O crystals in the kinetic mode has been in situ investigated for the...  相似文献   

9.
[La(OH2)5(phen)2]Cl3·4H2O·phen is centric, Pnna, witha=19.946(7),b=16.458(5),c=12.207(4)Å andD calc=1.57 g cm–3 forZ=4. The La(III) ion resides on a crystallographic twofold axis and is coordinated to four nitrogen atoms (from two phen molecules) and five water molecules resulting in a distorted tricapped trigonal prismatic geometry. An uncoordinated phen molecule, two chloride anions, and four uncoordinated water molecules are hydrogen bonded to the coordinated water molecules. The coordinated and uncoordinated phen molecules -stack diagonally through the unit cell.  相似文献   

10.
The title compound has been prepared by the addition of fluoroboric acid to 18-crown-6 in toluene. The compound crystallizes in the triclinic space group P¯1 witha=7.341(2),b=8.364(2),c=10.631(3)Å,=71.48(2),=67.91(2), =67.94(2)°, andD c =1.44 g cm–3 forZ=1. The final conventionalR value was 0.079 based on 1575 observed reflections. The molecule resides on a center of inversion. The (H2O·HBF4) moieties are best viewed as fluoroboric acid monohydrate molecules hydrogen bonded to the crown ether, one above and one below the plane of the crown. The FO(water) hydrogen bond separation is 2.474(5)Å, and the O(crown)O(water) separations are 2.834(5) and 2.841(6) Å. The oxygen atoms of the crown ether are planar to 0.23 Å.  相似文献   

11.
The complex Sr[CoII Edta] · 5H2O (I) (where Edta 4? is the ethylenediaminetetraacetate ion) has been synthesized. The crystal structure of this compound is determined by X-ray diffraction. Crystals are monoclinic, a = 7.906(2) Å, b = 12.768(2) Å, c = 18.254(3) Å, β = 95.30(3)°, V = 1834.8 Å3, space group P21/n, Z = 4, and R = 0.036. The structure is built up of the binuclear complex fragments {Sr(H2O)3[CoEdta(H2O)]}, which consist of the anionic [CoEdta(H2O)]2? and cationic [Sr(H2O)3]2+ units linked by the Sr-O bonds into a three-dimensional framework. The coordination polyhedra of the Co and Sr atoms are mono-and bicapped trigonal prisms. The coordination sphere of the Co atom (the coordination number is equal to 6 + 1) involves six donor atoms (2N and 4O) of the Edta 4? ligand and the Ow atom of water molecule. One of the Co-O distances (2.718 Å) is considerably longer than the other Co-Olig distances (2.092–2.190 Å) and the Co-Ow(1) distance (2.079 Å). The Sr coordination polyhedron (the coordination number is eight) contains three water molecules, three carbonyl O atoms of the three different anionic complexes, and two O atoms of one acetate group of the fourth anionic complex. The Sr-O distances fall in the range 2.535–2.674 Å. The structural formula of the compound is {Sr(H2O)3[CoEdta(H2O)]}3∞ · H2O.  相似文献   

12.
SrCd2Cl68H2O crystallizes in the space group and has the unit cell dimensions a = 9.688(2) Å, b = 11.212(2) Å, c = 7.732(3) Å, = 99.85(21)°, = 89.95(22)°, = 75.81(13)°, and Z = 2. After refinement through full-matrix least-squares methods, the reliability factor R in the final cycle is 4.65%. A very persistent occurrence of twinning by pseudosymmetry was observed. The twin element is a twofold axis [001]. The title compound exhibits five endothermic peaks, which have been detected by differential scanning calorimetry and interpreted from thermogravimetry.  相似文献   

13.
The title complex, [Co(phen)(H2O)4](SO4)2(H2O) (phen = 1,10-phenanthroline) was prepared in aqua tert-butylperoxohydrogen solution. X-ray single crystal structure determination reveals that the complex consists of a phenanthrolinatocobalt(II)tetrahydrate dication, two uncoordinated water molecules and a sulfate anion. It crystallizes in the orthorhombic space group Pbca with a = 8.856(1), b = 18.318(3), c =21.918(5) Å, V = 3555.6(11) Å3. The coordination geometry at each cobalt(II) atom is a slightly distorted octahedron.  相似文献   

14.
Single crystals of potassium uranyl sulfate are grown, and their atomic structure is determined using X-ray diffraction analysis. The compound crystallizes in the orthorhombic crystal system with space group Pna21 [a = 13.773(4) Å, b = 7.288(2) Å, c = 11.556(4) Å, R 1 = 0.033, wR 2 = 0.0892 for 2630 reflections with I > 2σ(I)]. The crystal structure of the K2UO2(SO4)2 · 2H2O compound is built up of two-dimensional infinite, negatively charged layers of the composition [UO2(SO4)2·H2O] 2∞ δ? ], which are linked together through the K+ ions. The specific features of the atomic arrangement in the structure of this compound are analyzed, and the second harmonic generation of laser radiation is investigated.  相似文献   

15.
The crystal structure of a highly hydrated tristrontium phosphate, nonastrontium hexakis(phosphate) hexadecahydrate, Sr9(PO4)6·16H2O, has been determined by single crystal X-ray diffraction. The crystals are monoclinic,a=15.203(2),b=6.488(1),c=18.984(7) Å, =98.42(2)o, space groupP2/c (No. 13),Z=2,V=1852.3 Å3,d c =2.951 Mg·m–3. The structure was refined by full-matrix least-squares techniques toR=0.038,R w =0.051, for 2329 reflections with I3(I). The structure can be described in terms of a layer-type arrangement parallel to (100). One layer consists of a compact assembly of columns of Sr and PO4 ions in a pseudohexagonal arrangement resembling an apatitic structure. A second layer containing all the water molecules and one PO4 ion that occupies the interstitial space may be referred to as the hydrated layer. The structure has an overall similarity to that of octacalcium phosphate and can be considered as a model for amorphous calcium phosphate.Certain commercial materials and equipment are identified in this paper to specify the experimental procedure. In no instance does such identification imply recommendation or endorsement by the National Institute of Standards and Technology or the ADA Health Foundation or that the material or equipment identified is necessarily the best available for the purpose.  相似文献   

16.
The new compound [Pd(NH2CH2CH2OH)4][Pd6(NH2CH2CH2S)8]Cl6 · 5H2O (I) is synthesized and its crystal structure is determined. The crystals are monoclinic, a = 25.625(6) Å, b = 9.633(5) Å, c = 24.847(7) Å, β = 91.47(2)°, Z = 4, and space group C2/c. The structural units of crystals I are the centrosymmetric hexanuclear [Pd6(NH2CH2CH2S)8]4+ cations, the mononuclear [Pd(NH2CH2CH2OH)4]2+ cations with C 2 symmetry, the Cl? anions, and crystallization water molecules. In the hexanuclear cation, the interaction between the Pd atoms occurs through the S atoms of the mercaptoethylaminate ligands. The Pd(2) and Pd(3) atoms and the ligands form two metallochelate fragments in which the N and S atoms are located in cis positions. The average lengths of the Pd-S and Pd-N bonds are equal to 2.274(1) and 2.074(6) Å, respectively. The metallochelate fragments are joined to each other and to their centrosymmetric analogues through the Pd(1) atom, which coordinates four S atoms [the average Pd-Sav bond length is 2.332(1) Å]. In the mononuclear cation, the Pd(4) atom coordinates four N atoms of the monoethylaminate ligands [the Pd-N bond lengths are 2.045(6) and 2.056(6) Å]. The shortest Pd?Pd distance is equal to 3.207(1) Å. The bonding in the structure is provided by numerous hydrogen bonds with the participation of all the H2O molecules, NH2 groups, and Cl? anions.  相似文献   

17.
Interest in superprotonic crystals of M m H n (XO4)(m + n)/2 is associated with the solution to the fundamental problem of modern condensed matter physics: investigations of structural phase transitions and the stabilization of phases with high proton conductivity with the aim of designing new functional materials. The available data suggest that changes in the physical properties in these crystals can occur through different structural mechanisms. To reveal the structural conditionality for anomalies in the physical properties, the crystals of K9H7(SO4)8 · H2O were studied by X-ray diffraction in the temperature range of 25–463 K, and the crystal structure of the high-temperature phase was determined at 418 K (sp. gr. Pcan). The results of the study indicate that the occurrence of high conductivity in K9H7(SO4)8 · H2O crystals at high temperatures is associated with the diffusion of water of crystallization, the hydrogen-bond network rearrangement, and the motion of K ions. The hydrogen-bond rearrangement and the hindered back diffusion of water to the crystal stabilize the high-temperature phase and ensure its supercooling to low temperatures.  相似文献   

18.
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   

19.
A new radical cation salt based on bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) with the tetrahedral anion GaCl 4 ? , namely, (BEDT-TTF)4(GaCl4)2 · C6H5CH3, has been synthesized. The crystal structure of this salt is determined by X-ray diffraction analysis [a = 31.757(2) Å, b = 6.8063(3) Å, c = 34.879(2) Å, β = 90.453(4)°, V = 7538.8(7) Å3, space group I2/c, and Z = 4]. In the structure, the radical cation layers alternate with the anion layers along the c-axis. The anion layers consist of the GaCl 4 ? tetrahedra and solvent molecules. The packing of BEDT-TTF molecules in the radical cation layer differs from that in the structure of the known salt (BEDT-TTF)2GaCl4, even though both compounds exhibit semiconductor properties.  相似文献   

20.
The synthesis and crystal structure ofbis(o-phenylenethiourea)selenium(II)-chloride dihydrate, Se(C7H6N2S)2Cl2·2H2O are reported. The compound crystallizes in the monoclinic space group, P21/n, with four molecules per unit cell, the dimensions of which area=10.243(3),b=13.341(4),c=14.273(4) Å,=93.00(3)°,U=1947.76 Å3. The structure was solved by direct methods and refined by full-matrix least-squares toR=0.039 andR w =0.040 for 3314 unique reflections. Selenium displays two strong coordinations arising from the two sulfurs, Se-S(1)=2.191(1), Se-S(2)=2.206(1) Å, and S(1)-Se-S(2)=101.0(1)°, and four secondary interactions involving three chlorines and one sulfur. The complex occurs as a dimer with two sets of very weakly interacting bridging pairs S(2), S(2)a; and Cl(2), Cl(2)a, where a denotes the inversion related atom. Lattice stabilization is ensured by the extensive network of hydrogen bonds involving chlorines, water oxygens, and nitrogens of phenylenethiourea ligands.  相似文献   

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