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Ca3Cl2CBN, a Compound with the New CBN4? Unit The new compound Ca3Cl2CBN was obtained from the reaction of Ca and CaCl2 with CaCN2, B and C or with BN and C, in sealed tantalum containers at 900°C. The crystal structure is related with the structure of Ca3Cl2C3 whereas the C34? units (C2v symmetry) are substituted by isoelectronic CBN4? anions (Cs symmetry): Ca3Cl2CBN, Pnma, a = 1 386.7(9) pm, b = 384.7(3) pm, c = 1 124.7(6) pm, Z = 4; R = 0.055, Rw = 0.036 for 380 independent intensities. The CBN4? units are located between layers of Ca2+ that are interconnected by Cl?. The bond angle (C? B? N) is 176° and bond distances are dC? B = 144 pm and dB? N = 138 pm, respectively.  相似文献   

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Ba4FeTa10O30, a New Compound with Relations to the NaNb6O15F-Type Ba4FeTa10O30 was prepared by high temperature reactions (CO2-Laser-technique) and investigated by X-ray single crystal studies (space group C2v14–Amm2, a = 3.906, b = 10.201, c = 14.990 Å, Z = 1). The new compound has a tunnel structure, related to the tungsten bronzes, but with more relationship to the NbO6-octahedra network of NaNb6O15F.  相似文献   

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Bismuth Monoiodide, a Compound with Bi(O) and Bi(II) Bismuth monoiodide was synthesized in closed tubes from the elements as well as from Bi and HgI2 as a black coloured crystalline compound. With increasing temperature BiI passes two transitions. α-BiI is stable below 370 K and changes to β-BiI by a martensitic transition. γ-BiI is the stable modification above 564 K and decomposes at 585 K peritectically to BiI3 and a lower iodide. All three modification crystallize in the monoclinic space group C2/m. The structures (single crystal studies) of α-BiI and β-BiI are characterized by onedimensional infinite chains [Bi4I4] with covalent bonds but only weak interactions in between. The [Bi4I4]-chains are built up by two completely different Bi atoms. Bi(A) is only bonded to three Bi whereas Bi(B) has bonds to one Bi and four I. The average bond lengths are Bi? Bi = 304.5 pm and Bi? I = 313.7 pm respectively. The configuration of the Bi(A) atoms is typical for BiO and that one of the Bi(B) atoms is characteristic for Bi2+ with the electron configuration s2p1. Therefore, α-BiI and β-BiI are mixed valence compounds [BiOBi2+I4]. The structures are variants of the simple cubic polonium type of structure and differ in the stacking of connected units. The structures and their transitions, the possible configurations for monohalides BiX on principle as well as the energy balances of the disproportionation of Bi+ are discussed together in detail.  相似文献   

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On Oxidesulfides of Åkermanitetype-Structure CaLaGa3S6O, SrLaGa3S6O, La2ZnGa2S6O, and Sr2ZnGe2S6O The oxide sulfides were prepared for the first time (space group and lattice constants see “Inhaltsübersicht”). The atomic positions were refined from single crystal X-ray data for CaLaGa3S6O and La2ZnGa2S6O. Problems concerning the metal distribution on the crystallographic positions are discussed by comparing interatomic distances. The ratio c/a of the new compounds is compared with that of isotypic compounds from literature.  相似文献   

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Synthesis and X-Ray Structure Analysis of the 8π-Electron-Ring-System S4N4O2Sn2(CH3)6 and the Magnetic Properties of S4N4O2 and S8N8O4 S4N4O2 reacts with N[Sn(CH3)3]3 in a molar ratio of 1:1 to an eight-membered trimethyltin-substituted 8π-electron skeleton, S4N4O2Sn2(CH3)6. In contrast to known 6π-electronsystems this compound has tin atoms which are tetracoordinated. This was demonstrated on the basis of an x-ray analysis. S4N4O2Sn2(CH3)6 · 1/2 C6H6 crystallizes in the space group P21/c with a = 1396.0(4), b = 1190.3(4), c = 1256.7(3) pm, and β = 103.46(2)°. It was shown that the ability of coordination at the tin atom depends on the electron density. The magnetic properties of S4N4O2 and S8N8O4 were investigated by the Faraday method. The high diamagnetism in these ring compounds is caused by the π-electrons.  相似文献   

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CsPdCl3 – A Compound with Isolated [Pd2Cl6] Groups and an Inorganic Cation The crystal structure of CsPdCl3 has been characterized by X-ray powder diffraction methods. Meanwhile it was possible to isolate single crystals and to confirm the structure by single crystal X-ray investigations. CsPdCl3 crystallizes orthorhombic in space group Ibam (No. 72) with a = 13.724(1), b = 10.579(1), c = 8.499(1) Å, and Z = 8. CsPdCl3 is a compound with a dinuclear [Pd2Cl6]2– group and a cesium cation. Formerly such groups are only found in combination with large “organic” cations so far.  相似文献   

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CsCu5S3 – A New Compound existing in two Modifications CsCu5S3 has been obtained in form of two modifications in a flux of cesium thiocyanate. Single crystal investigations revealed a tetragonal modification closely related to the structure of TlCu5Se3. The orthorhombic crystallizing modification can be described as a layer structure. The copper atoms in both atomic arrangements form arrays (fragment frame structures) of the fcc copper structure. At 582 °C the orthorhombic modification transforms easily into the tetragonal one, while the reverse reaction occurs very slowly.  相似文献   

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Zusammenfassung Eine kurze Übersicht über die Struktur der verschiedenen Verbindungen vom Typus des -Al2O3 wird gegeben und ein Vergleich mit dem Mineral Magnetoplumbit vorgenommen. Es wird die Ansicht vertreten, daß sämtliche Verbindungen des -Typus analog kristallisieren wie Magnetoplumbit. Die Alkali- und auch Erdalkali-Ionen können aber teilweise aus dem Gitter entfernt werden, wodurch die wechselnden analytischen Ergebnisse bedingt sind. Ein bisher fehlendes Glied in der Reihe der -Verbindungen mit der Zusamensetzung PbO·6 Al2O3 wurde dargestellt und beschrieben. Diese als Blei--Al2O3 bezeichnete Verbindung stellt ein direktes Analogon zu Magnetoplumbit dar.
The structures of various compounds of the type of -Al2O3 are reviewed, and compared with the mineral magnetoplumbite. The opinion is advocated that all compounds of the type of -Al2O3 crystallize analogous to magnetoplumbite. The ions of the alkali metals and alkaline earths can, however, partially be removed from the lattice, thereby leading to the various analytical compositions. One as yet missing link in this line of -compounds of the composition PbO· 6 Al2O3 was synthesized, and is described. this Lead--Al2O3 is a directly analogous to magnetoplumbite.
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Improved Syntheses, Crystal Growth, and Crystal Structure Determination of P4O6S2 and P4O6S3 Syntheses and single crystal growths of the title compounds are described. Both compounds crystallize in the space group P21/c (P4O6S2: a = 11.293(4); b = 6.457(3); c = 11.588(4) Å; β = 90.29(2)°, 2 450 diffractometer data, Rw = 0.035/P4O6S3: a = 15.611(5); b = 8,303(3); c = 9.697(4) Å; β = 127.12(2)°, 2 481 diffractometer data, Rw = 0.034). The structural data for the series P4O6Sn (n = 1 – 4) thus completed are compared to their oxide analogues P4O6On (n = 1 – 4). The changes in the geometry of the P4O6-cage in course of its successive oxidation are discussed.  相似文献   

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[Cl3PNPCl3][MoNCl4], a Compound having Columns of Stacked Anions The title compound is formed by the reaction of [Cl3PNPCl3]Cl with MoNCl3 in CH2Cl2 and subsequent precipitation with CCl4 in from of orange-red crystals. According to the 31P-NMR spectrum, the compound exists as its isomer phosphaneiminate [Cl5Mo(NPCl2NPCl3)] in CD2Cl2/CH3CN solution. The crystal structure of [Cl3PNPCl3][MoNCl4] is isotypic with that of [Cl3PNPCl3][MoOCl4] and shows the same kind of two-dimensional disorder. X-ray diffraction patterns show planes of diffuse scattering as well as Bragg reflexions. The latter correspond to an averaged structure with a = 1590.0, b = 1141.6, c = 418.0 pm, space group Pba2, Z = 2. In the averaged structure (606 reflexions, R = 0.071) the atom sites have fractional occupation. The real structure consists of square-pyramidal [MoNCl4]? ions stacked to form columns with alternating MoN distances of 175 and 243 pm. The packing of the columns is disordered in that the [MoNCl4]? pyramids point either in the +c or ?c direction. The [Cl3PNPCl3]+ ions are stacked in the c direction and show two types of disorder, namely a displacement parallel to c and a rotation by 120° about the P? P axis.  相似文献   

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Chemistry and Structural Chemistry of Phosphides and Polyphosphides. 26. Dibariumheptaphosphidechloride Ba2P7Cl, a Compound with the Polycyclic Anion P Ba2P7Cl is formed by the synthesis of Ba3P14 from the elements in a melt of BaCl2 (dehydrated) at 1170 K. The compound forms light rubyred platelets which decompose in protic systems immediately to phosphanes. Ba2P7Cl crystallizes in the space group P21/m with Z = 2 formular units (a = 1172.6(2) pm; b = 682.9(1) pm; c = 633.7(1) pm; β = 95.27(2)°). The structure (964 reflexions hkl, R = 0.035) is related to the NaCl type, in which the half of the anionic positions is occupied by the gravi-centers of the polycyclic anions P. The bond lengths d(P? P) show the typical topological dependence for the anionic heptaphosphanortricyclene system: (d : 226.4 pm in the three-membered ring; 214.5 pm ring to bridge; 217.2 pm bridge to bridge head). The Ba atoms are surrounded by 9 and 10 non metallic atoms, respectively. Cl? is coordinated tetrahedrally by Ba.  相似文献   

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The New Layer‐Silicates Ba3Si6O9N4 and Eu3Si6O9N4 The new oxonitridosilicate Ba3Si6O9N4 has been synthesized in a radiofrequency furnace starting from BaCO3, amorphous SiO2 and Si3N4. The reaction temperature was at about 1370 °C. The structure of the colorless compound has been determined by single‐crystal X‐ray diffraction analysis (Ba3Si6O9N4, space group P3 (no. 143), a = 724.9(1) pm, c = 678.4(2) pm, V = 308.69(9)· 106 pm3, Z = 1, R1 = 0.0309, 1312 independent reflections, 68 refined parameters). The compound is built up of corner sharing SiO2N2 tetrahedra forming corrugated layers between which the Ba2+ ions are located. Substitution of barium by europium leads to the isotypic compound Eu3Si6O9N4. Because no single‐crystals could be obtained, a Rietveld refinement of the powder diffractogram was conducted for the structure refinement (Eu3Si6O9N4, space group P3 (no. 143), a = 711.49(1) pm, c = 656.64(2) pm, V = 287.866(8) ·106 pm3, Rp = 0.0379, RF2 = 0.0638). The 29Si MAS‐NMR spectrum of Ba3Si6O9N4 shows two resonances at ?64.1 and ?66.0 ppm confirming two different crystallographic Si sites.  相似文献   

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