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1.
The Crystal Structure of CsTcO4 CsTcO4 crystallizes orthorhombic with a = 5.727, b = 5.921 and c = 14.34 Å. Z = 4, space group Pnma (Nr. 62, I.T.). The metal positions were refined by single crystal data, the oxygen positions first determined: the CsTcO4 structure is a slight distortion of the scheelite arrangement (parameters: see text). The MADELUNG Part of Lattice Energy, MAPLE, ?Mean Effective Ionic Radii”?, MEIR, and Effective Coordination Numbers, ECoN, are calculated and discussed.  相似文献   

2.
Crystal structure of AgIIF[AgIIIF4] For the first time dark brown single crystals of mixedvalent AgF[AgF4] were isolated under solvothermal conditions out of anhydrous HF/F2. The compound crystallizes in a new type of structure, triclinic with a = 499.9(2) pm, b = 1108.7(5) pm, c = 735.7(3) pm, α = 90.05(3)°, β = 106.54(4)°, γ = 90.18(4)°, spcgr. P1¯ — Ci1 (No. 2) and Z = 4.  相似文献   

3.
The Crystal Structure of Antimony Tetrachloride Cyanurate [SbCl4NCO]3 [SbCl4NCO]3 crystallizes in the hexagonal space group P63/m with two formula units per unit cell; the lattice parameters are a = 1167 and c = 995 pm. The crystal structure was solved with X-ray diffraction data by means of a Patterson and a Fourier Synthesis and was refined by the method of least-squares to a reliability index of R = 3.6% for the 863 observed reflexions. The structure consists of [SbCl4NCO]3 molecules having the point symmetry 6 . The molecule is a derivate of cyanuric acid in a way such that each Sb atom is bonded in chelate manner by one N and one O atom; together with 4 Cl atoms the antimony attains a distorted octahedral coordination. The packing density in the crystal is not optimal, there exist cavities.  相似文献   

4.
The crystal structure of Si5O[PO4]6 has been determined and refined by least-squares, using three-dimensional X-raydata fromWeissenberg photographs: space group R 3;a=7.869 andc=24.138 Å;Z=3; 418 independent reflections;R=6.0%. The crystal structure consists of isolated [SiO6] octahedra and [Si2O7] groups which are linked by [PO4] tetrahedra forming a three-dimensional network. The average interatomic distances are: Si[6]?O=1.768, Si[4]?O=1.607 and P?O=1.52i Å. The compound is isotypic with Ge5O[PO4]6.  相似文献   

5.
Zusammenfassung Die Kristallstruktur der Verbindung Ge5O[PO4]6 wurde auf Grund dreidimensionaler Einkristalldaten ausWeissenberg-Aufnahmen ermittelt und nach der Methode der kleinsten Quadrate verfeinert: Raumgruppe ;a=7,994±0,004 undc=24,87±0,01 Å;Z=3; 467 unabhängige Reflexe;R=0,086.Die Kristallstruktur wird aus singulären [GeO6]-Oktaedern und [Ge2O7]-Doppeltetraedern aufgebaut, die über [PO4]-Tetraeder zu einem dreidimensionalen Strukturverband vernetzt sind. Die mittleren Abstände betragen: Ge[6]–O=1,863, Ge[4]–O=1,704 und P–O=1,525 Å.
The crystal structure of Ge5O[PO4]6
The crystal structure of Ge5O[PO4]6 has been determined and refined by least-squares, using three-dimensional x-ray data fromWeissenberg-photographs: space group ;a=7.994±0.004 andc=24.87±0.01 Å;Z=3; 467 independent reflections;R=0.086.The crystal structure consists of isolated [GeO6] octahedra and [Ge2O7] double tetrahedra which are linked by [PO4] groups forming a three-dimensional network. The average interatomic distances are: Ge[6]–O=1.863, Ge[4]–O=1.704 and P–O=1.525 Å.


Mit 2 Abbildungen  相似文献   

6.
Investigations on Electronically Conducting Oxide Systems. XIV. Solid Solutions and Conductivity in the System MgTiO3? Ti2O3 Solid solution formation and conductivity is reported for the system Mg1?xTiTiO3 (0 < x < 1). TiIII atoms are predominantly substituted in pairs for MgII and TiIV. In the range of low x values TiIII? TiIII bonds typical for Ti2O3 in the semiconducting state are very weakened because of the distances preserved in the host lattice of MgTiO3. Up to x = 0,5 EPR measurements at 77 K indicate magnetic “dimers” with S = 1 at a distance of 550 pm resulting from antiparallel spin orientation of the TiIII pairs and transfer of the magnetic interaction by super exchange to a next-neighboured TiIII pair. Electrical conductivity is caused by polaron hopping. The steep increase in the range of small TiIII concentration is interpreted by a screening field approximation.  相似文献   

7.
Diorganoindium Cations. The Crystal Structure of [Mes2In][BF4] (PhCH3)2In and Mes3In react with BF3 · OEt2 in a ratio of 3:4 at 80°C in toluene to the corresponding salts [R2In][BF4] [R = PhCH2 ( 1 ), Mes ( 2 )]. The same results could be obtained, when the diorganoindium fluorides (PhCH2)2InF and Mes2InF were treated with BF3 · OEt2 at 80°C in toluene. 1 und 2 were characterized by NMR-, IR- und MS-techniques. The arrangement of the ions in 2 could be established by an X-ray structure determination. The cations and anions of 2 are forming infinite chains. The metal centers are coordinated by two BF4?-ions, so that every In atom possesses a distorted octahedral coordination sphere.  相似文献   

8.
Crystal Structure of (AsPh4)2[W2NCl10] The title compound is formed by a slow reaction of AsPh4[WNCl4] in acetonitrile solution in form of dark brown crystals. The crystal structure was solved by X-ray diffraction methods (R = 4.7%; 1461 observed, independent reflexions). (AsPh4)2[W2NCl10] crystallizes in the monoclinic space group P21/n with two formula units per unit cell. The structure consists of AsPh4θ and [W2NCl10] ions. The tungsten atoms with oxidation numbers five and six respectively, are linked by a linear, asymmetric nitrido bridge (r WN = 171 and 203 pm). The trans-effect of the W? N-multiple bonds causes a significant difference between axial (W? Clax 243 pm) and equatorial (mean W? Cleq 230 pm) bond lengths.  相似文献   

9.
10.
The crystal structure of 1,2,3,4-Tetrahydro-1-methyl-2-oxopyrimido[1,2-a]benzimidazol-4-carboxylicacid-methylester was investigated by an X-ray analysis in order to determine unequivocally the positions of the substituents. The triclinic structure was solved by the multisolution method and refined to an R = 0.0302 with 1486 structure factors for 222 structural parameters.  相似文献   

11.
12.
Zusammenfassung Die Kristallstruktur des Lithiumorthosilicats wurde mittels dreidimensionaler Fourier-Synthesen und nach der Methode der kleinsten Quadrate bestimmt. Die Gitterparameter der monoklinen Elementarzelle (C 2h 2 –P21/m) betragen:a=5,14;b=6,10;c=5,30 Å und =90,5°. Die Struktur enthält isolierte [SiO4]-Tetraeder, welche durch [LiO n ]-Polyeder (n=4, 5, 6) verknüpft sind. Hervorzuheben ist, daß sämtliche Lithiumlagen nur partiell besetzt sind. Als mittlerer Si–O-Abstand wurde 1,632 Å erhalten; als Mittelwerte der Li–O-Abstände für die verschiedenen Koordinationszahlen ergeben sich: 1,975 [4]; 2,099 [5] und 2,247 [6] Å.
The crystal structure of lithium orthosilicate has been determined by means of three-dimensional Fourier syntheses and the least squares method. The lattice parameters of the monoclinic unit cell (P21/m–C 2h 2 ) are:a=5.14;b=6.10;c=5.30 Å and =90.5°. The crystal structure contains isolated [SiO4]-tetrahedra being connected by [LiO n ]-polyhedra (n=4, 5, 6). The positions of the lithium atoms are partially occupied only. The average interatomic Si–O distance is found to be 1.632 Å. The averaged values for Li–O distances given for the different coordination numbers are: 1.975 [4]; 2.099 [5] and 2.247 [6] Å.


Mit 4 Abbildungen  相似文献   

13.
Reactions of Zirconium Tetrachloride with Trithiazylchloride. Crystal Structure of (S4N4)[Zr2Cl10] Zirconium tetrachloride reacts with (NSCI)3 yielding (S3N3CI2)2[Zr2CI10], S4N4[Zr2CI10], or (S4N4CI)2[Zr2CI10], depending of the reaction conditions. These compounds were characterized by their i.r. spectra. They have an ionic structure containing the known ions S3N3CI2⊕, S4N42⊕, S4N4CI, and the thus far unknown [Zr2CI10]2? ion. According to the X-ray structure determination (2827 independent observed reflexions, R = 0.027), (S4N4CI)2[Zr2CI10] crystallizes in the space group P&1macr; with the lattice constants a = 688, b = 1132, c = 1827 pm, α = 103.2°, β = 98.7° and γ = 91.90 and with Z = 2 formula units per unit cell. The structure is built up from S4N4CI ions, which are nearly identical as in S4N4CI[FeCI4] and from [Zr2CI10]2? ions in which two chloro bridges join two edge-sharing octahedra.  相似文献   

14.
Preparation and Crystal Structure of K4[SnO3] K4[SnO3] crystallizes with the K4[PbO3] structure in the orthorhombic spacegroup Pbca (No. 61) with the lattice constants a = 652.2(3) pm, b = 1 112.1(5) pm and c = 1 893.7(7) pm. In the structure isolated ψ-tetrahedral anions [SnIIO3]4? are arranged in layers perpendicular [001]. The structure of K4[SnO3] will be compared with those of stannates and plumbates of composition A4[MIIO3] (A = Na, K, Rb, Cs) and with the known potassium stannates(II).  相似文献   

15.
Crystal Structure of Anhydrous Na2HPO4 Na2HPO4 crystallizes monoclinic in P21/m? C with: a = 545.(1), b = 684.7(2); c = 547.3(1) pm; β = 116.34(1)°; Z = 2. The structure consists of a nearly hexagonal close-packed arrangement of HPO42? anions with Na+ in the “octahedral” and “tetrahedral” holes. The anions are orientationally disordered. Structural relationships with Na2SO4(III) and the glaserite-type of structure are discussed.  相似文献   

16.
The crystal structure of the title compound has been determined from single crystal X-ray diffraction data and refined toR=0.125. The unit cell is triclinic, space group P, (No. 2),a=5.688(1),b=5.701(1),c=8.583(1) Å, =81.32(1), =71.50(1), =67.95(1)° andZ=2. The structure consists of isolated [GeO4] tetrahedra linked together by four- and five-coordinate sodium atoms. Na4GeO4 is isostructural with Na4CoO4 (which has been described to be non-centrosymmetric and for which a centrosymmetric model is presented), K4GeO4, K4SnO4 and K4PbO4.
  相似文献   

17.
Zusammenfassung Die Kristallstruktur der Verbindung LiNa[Ge4O9] wird durch dreidimensionale Patterson- und Fourier-Synthesen bestimmt und mit Hilfe der Methode der kleinsten Quadrate verfeinert. Die rhombische Elementarzelle (Pcca-D 2h 8 ) mit den Abmessungen:a=9,31,b=4,68,c=15,88 Å enthält 4 Formeleinheiten. Die Struktur wird aus [GeO3] n -Ketten mit tetraedrisch koordiniertem Germanium aufgebaut, die über [GeO6]-Oktaeder zu einem dreidimensionalen Gerüst vernetzt sind. Als mittlere interatomare Ge-O-Abstände wurden erhalten: 1,758 [4] und 1,866[6] Å. Die Verbindung LiNa[Ge4O9] stellt ein Endglied der Mischreihe Li2–x Na x [Ge4O9] dar.
Crystal structure of LiNa[Ge4O9]
The crystal structure of LiNa[Ge4O9] has been determined by means of three-dimensional Patterson and electron density syntheses and refined by least-squares methods. The orthorhombic unit cell (Pcca-D 2h 8 ) having the lattice parametersa=9.31,b=4.68 andc=15.88 Å contains 4 formula units. The crystal structure consists of [GeO3] n -chains of tetrahedrally coordinated Ge-atoms which are connected by [GeO6]-octahedra to form a three-dimensional framework. The interatomic Ge-O-distances are found to be 1.758[4] and 1.866[6] Å. The compound LiNa[Ge4O9] represents a member of the solid solution series Li2–x Na x [Ge4O9].
  相似文献   

18.
Reaction of Trithiazyl Chloride with Titanium Tetrachloride. Crystal Structure of (S4N5)2[Ti2Cl10] In the reaction of trithiazyl chloride with titanium tetrachloride, chlorine is abstracted and the brown-yellow adduct TiCl4(N2S2) is obtained. In this compound — according to its i.r. spectrum — a N2S2 ring is bonded to the titanium via the N atoms, thus forming a polymer. As a by-product, brown crystalline (S4N5)2[Ti2Cl10] forms. Its crystal structure was determined and refined with X-ray diffraction data (R = 0.042 for 812 reflexions). It crystallizes in the monoclinic space group P21/c with two formula units per unit cell. The lattice constants are a = 670, b = 1 633, c = 1108 pm, β = 97.24°. The structure consists of S4N5 cations, which are nearly equal to those in [S4N5]Cl, and [Ti2Cl10]2? anions, which are nearly identical with those in (PCl4)2[Ti2Cl10].  相似文献   

19.
Thionitrosyl Complexes of Osmium. Crystal Structure of AsPh4[OsCl4(NS)2Cl] The reaction of osmium pentachloride with trithiazyl chloride (NSCl)3 yields the thiazylchloride complex [OsCl4(NSCl)2], from which the thionitrosyl complex AsPh4[OsCl4(NS)2Cl] is obtained by reaction with AsPh4Cl in CH2Cl2. From this, the neutral thionitrosyl complex [OsCl4(NS)2] forms by chloride abstraction with gallium trichloride. The crystal structure of AsPh4[OsCl4(NS)2Cl] was determined and refined with the aid of X-ray diffraction data (R = 0.033, 2161 reflexions). It crystallizes in the monoclinic space group P21/c with four formula units per unit cell. The lattice constants are a = 1735, b = 1058, c = 1578 pm and β 95.64°. In the [OsCl4(NS)2Cl]? ion the osmium is octahedrally coordinated by four Cl atoms and two NS groups in a cis arrangement. The NS groups are essentially linear with the bond lengths Os?N 184 pm and N?S 146 pm. Loosely attached to one of the S atoms there is a Cl atom (S? Cl distance 228 pm); in the crystal it statistically belongs to both S atoms with an occupation probability of one half, and it cannot be decided whether there is a dynamical fluctuation between the S atoms or a static positional disorder. However, according to the i.r. spectrum the dynamical model seems more probable.  相似文献   

20.
On Na4(CrO4) Dark-green single crystals of Na4[CrO4] were obtained for the first time. (Na2O/Cr2O3; Na:Cr = 4:1 not exactly closed Ni-tube; 1000°C; 30 d). It is isostructural to Na4(CoO4); space group P1 , a = 859.7 pm, b = 569.8 pm, c = 640 pm, α = 124°C, β = 98.4°, γ = 98.9°, Z = 2. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.  相似文献   

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