Die Kristallstruktur der Tieftemperaturmodifikation von Ag5Te2Cl

The Crystal Structure of the Low‐Temperature Form of Ag₅Te₂Cl Crystals of trimorphic Ag₅Te₂Cl were obtained by solid state reaction from a stoichiometric mixture of silver, tellurium, and tellurium(IV)chloride (480 °C, 4–10 days). The crystals were cooled down to –80 °C without decomposition and data collection was carried out at this temperature. The low temperature form of the title compound crystallizes in space group P2₁/c with lattice constants of a = 19.359(1) Å, b = 7.713(1) Å, c = 19.533(1) Å, β = 90.6°(1), V = 2916.4(1), and Z = 16. The refinement converged to residual values of R₁ = 0.0381 and wR₂ = 0.0847, respectively. Te and Cl atoms form empty, distorted octahedra interconnected by common vertices to give a 3D‐network. Ag atoms form clusters with Ag–Ag distances between 2.83 Å and 3.10 Å.     

Kristallstruktur der Tieftemperaturmodifikation von RuTe2

Crystal Structure of the Low Temperature Modification of RuTe₂ Black shining, platelet like single crystals of α-RuTe₂ were obtained by chemical transport reaction with Cl₂/AlCl₃ (crystal dimensions up to 1 mm). The crystal structure of this low temperature modification of α-RuTe₂ hitherto only known from powder measurements, was redetermined at room temperature by single crystal X-ray diffraction on a four-circle diffractometer. α-RuTe₂ crystallizes in the marcasit structure typ in the orthorhombic spacegroup Pnnm (No. 58) with the lattice constants a = 528.12(13), b = 639.43(19), c = 400.85(13) pm.     

Die Kristallstruktur von Li8PbO6

Crystal Structure of Li₈PbO₆ The crystal structure of Li₈PbO₆ (Li₈TbO₆ structure, space group R3 ? C, hexagonal lattice constants a = 554.3, c = 1 563 pm) has been refined by profile analysis of a neutron diffraction pattern. Deviations from ideal tetrahedral and octahedral coordination of lithium atoms are similar to those described for Li₈SnO₆.     

Die Kristallstruktur von Ag3Co(CN)6

The crystal structure of the hexagonal Ag₃Co(CN)₆ (a = 7.03 Å, c = 7.13 Å, Z = 1) has been determined by X-ray powder methods. The structure factor calculations based on the space group D lead to a reliability index R of 0.062, the R̃-value from F²-sums of systematically coinciding reflections being 0.064. The cobalt atoms are located in the position 1 a (0,0,0), the silver atoms in 3g (1/2,0,1/2;0,1/2,1/2;1/2,1/2,1/2). The carbon and nitrogen atoms occupy the position 6k. The interatomic distance are: Co-C = 1.89 Å, C-N = 1.14 Å, Ag-N = 2.06 Å. The angle C-N-Ag is 157.3º.     

Die Kristallstruktur von Gd6Cu8Ge8 und isotypen Phasen

Zusammenfassung Die Verbindungen Gd(Dy, Er, Lu)₆Cu₈Ge₈ wurden hergestellt und ihre Struktur bestimmt. Gd₆Cu₈Ge₈ kristallisiert orthorhombisch in einem neuen Strukturtyp mita=14,000±0,008 Å,b=6,655±0,003 Å,c=4,223±0,004 Å, Raumgruppe D _2h ²⁵ -I mmm mit 2 Gd in 2 (d), 4 Gd in 4 (e), 8 Cu in 8 (n), 4 Ge in 4 (f) und 4 Ge in 4 (h), N=1. Die Struktur ist durch Verwandtschaft zum AlB₂- und CaZn₅-Typ gekennzeichnet. Die anderen genannten Phasen sind dem Gd₆Cu₈Ge₈ isotyp.

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Crystal structure of Gd₆Cu₈Ge₈, and of isotypic phases

The compounds Gd(Dy, Er, Lu)₆Cu₈Ge₈ have been prepared and their structure has been determined. Gd₆Cu₈Ge₈ crystallizes in a new structure type witha=14.000±0.008 Å,b=6.655±0.003 Å,c=4.223±0.004 Å, space group D _2h ²⁵ -I mmm with 2 Gd in 2 (d), 4 Gd in 4 (e), 8 Cu in 8 (n), 4 Ge in 4 (f) and 4 Ge in 4 (h), N=1. The structure is characterized by close relationship to the AlB₂ and CaZn₅ structure types. The other phases mentioned above are isotypic to Gd₆Cu₈Ge₈.

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Die Verfeinerung der Kristallstruktur von ThOTe

Refinement of the Crystal Structure of ThOTe The crystal structure of ThOTe has been refined with single crystal data. The compound crystallizes in a PbFCl-type arrangement (space group P4/nmm, a = 412.8(2) pm, c = 755.8(7) pm, z(Th) = 0.17081(6), z(Te) = 0.6348(1)).     

Die Kristallstruktur von KPr3Te8

Crystal Structure of KPr₃Te₈ Out of the compounds ALn₃Q₄ (A = Na, K, Rb, Cs; Ln = Lanthanoid; Q = S, Se and Te) the crystal structure of the telluride KPr₃Te₈ was determined by X‐ray single‐crystal structure analysis. Single crystals of the compound were synthesized by a flux technique with K₂Te₃ as flux after separation of the K₂Te₃ excess by extraction with absolute dimethylformamide (DMF). The compound crystallizes monoclinically in space group P12₁/c1 with the lattice parameters a = 1390.58(7) pm, b = 1291.06(6) pm, c = 900, 18(5) pm and β = 99, 264(6)° isotypically to KNd₃Te₈. Characteristics in the crystal structure of KPr₃Te₈ are L‐shaped units of three tellurium atoms [Te₃]^2— as well as infinite zig‐zag chains of tellurium atoms [Te₄]^4—. The shortest interatomic distances in the chain are alternating only slightly with 298 and 300 pm and are in the range of partial bonds. Both structure elements are arranged in almost planar layers and are interconnected with each other by secondary interactions revealing interatomic distances in the range of 327 to 349 pm. The crystal structure of KPr₃Te₈ can be regarded as a addition‐defect variant of the binary NdTe₃ structure type. This finding is illustrated by group‐subgroup relations in form of a so called Bärnighausen family tree.     

Die Kristallstruktur der Subcarbide von Übergangsmetallen

Ohne ZusammenfassungMit 4 Abbildungen     

Neutronenbeugung an der Tieftemperaturmodifikation von Rubidiumdeuteroamid

Neutron Diffraction of the Low Temperature Modification of Rubidium Deutero Amide A polycrystalline sample of RbND₂ was prepared by reaction of liquid ND₃ and Rb (320 K, 4 d). Rietveld refinement of neutron powder diffraction data collected on the E2 (HMI-BENSC, Berlin) yielded the deuterium positions and allowed the temperature factors of all atoms to be refined anisotropically: space group P2₁/m, Z = 2, a = 4.846(1) Å, b = 4.136(1) Å, c = 6.396(2) Å, β = 98.051(7)°, N(I/σ_(I) > 1) = 179, N(Var.) = 25, R_P = 0.025, wR_P = 0.032, R_B(I/σ_(I) > 1) = 0.095. In a monoclinic distorted rock salt structure the amide ions are oriented antiferroelectrically in almost planar zick-zack chains.     

Die Kristallstruktur von Cs2NaInF6

Using single crystal data the occurence of the K₂NaCrF₆ type of structure for Cs₂NaInF₆ (a = 8.905 Å) has been confirmed and x_F determined to be x_F = 0.229; in consequence: In–F = 2.03₉ Å [430 (hkl) with h + k = 2n and h = 0 to 7; R = 11.1%; Mo? K_α.]. The Madelung Part of Lattice Energy is calculated and discussed in detail.     

Die Kristallstruktur von Ag2TeO2(OH)4

Zusammenfassung Die Kristallstruktur von Ag₂TeO₂(OH)₄ wurde mit Hilfe von Einkristallmethoden bestimmt und nach der Methode der kleinsten Quadrate verfeinert. Die Gitterparameter der Elementarzelle (Fdd 2–C _2v ¹⁹ ) betragen:a=18,72;b=6,48;c=8,94 Å. Mit allen beobachteten Reflexen wurde einR-Wert von 8,50%, unter Einschluß derHamilton-Reflexe einR-Wert von 9,41% erhalten. Die Telluratome sind oktaedrisch von 6 Sauerstoffen umgeben, während die Silberatome stark verzerrt tetraedrisch von 4 Sauerstoffen umgeben sind. Zwei dieser Tetraeder bilden mit einem dazwischenliegenden Oktaeder eine geometrische Einheit. Diese Einheiten sind über Sauerstoffe, die zu zwei verschiedenen Tetraedern gehören, und über Wasserstoffbrücken zu einem dreidimensionalen Gerüst verknüpft.

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The crystal structure of Ag₂TeO₂(OH)₄

The crystal structure of Ag₂TeO₂(OH)₄ has been determined by single crystal X-ray methods and refined by the least squares method. The lattice parameters of the cell (Fdd 2–C _2v ¹⁹ ) are:a=18.72;b=6.48;c=8.94 Å. With all observed reflections anR-Value of 8.50% was obtained; if allHamilton-reflections are includedR=9.41%. The Te atoms are surrounded octahedrally by 6 oxygens, the 4 oxygens around the silver atoms form a distorted tetrahedron. Two of these tetrahedra form with an intermediate octahedron a geometric unit. These units are linked together to a three-dimensional structure by oxygens belonging to two different tetrahedra and by hydrogen bondings.

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Zur Kenntnis der NaCl-Strukturfamilie Die Kristallstruktur von NaMnO2

To the Knowledge of the NaCl Family of Structure: The Crystal Structure of NaMnO₂ Ochre coloured single crystals of NaMnO₂ show a monoclinic [a = 5.662 Å, b = 2.860 Å, c = 5.799 Å, β = 113.1°] variant [C–C2/m; Na in 2(d), Mn in 2(a), O in 4(i), R = 11.2% (MoK_α)] of the α-NaFeO₂-type of structure. The Jahn-Teller-distortion within the {MnO₆}-Group ist remarkable with Mn ? O = 1.93 (4×), 2.40 (2 ×) Å. NaMnO₂ posesses temperature indepent paramagnetism: +_Mol =+3450 · 10^?6 cgs. The Madelung Part of Lattice Energy is calculated and discussed.     

Die Kristallstruktur von Thalliumtrifluorid

The crystal structure of thallium trifluoride The crystal structure of TlF₃ has been determined form single crystal diffraction data. The unit cell is orthorhombic, space group Pnma≠D, with a = 5.825, b = 7.024, c = 4.851 Å, Z = 4. Each Tl has 8 nearest F-neighbours. The Tl–F distances range from 2.09 to 2.49 Å.     

Die Kristallstruktur von Kaliummonomethylcarbonat

Crystal Structure of Potassium Monomethylcarbonate Potassium monomethylcarbonate KCH₃CO₃ was obtained from reaction of dimethylcarbonate with potassium hydroxide in methanole. The crystal structure was determined (triclinic, P1 (no. 2), Z = 2, a = 380.9(2) pm, b = 558.9(3) pm, c = 985.3(3) pm, α = 100.71(2)°, β = 90.06(3)°, γ = 92.48(3)°, V = 205.9(2) · 10⁶ pm³, wR(F²) = 0.054, wR_obs(F) = 0.022). Structural relations between potassium monomethylcarbonate and potassium hydrogencarbonate are discussed.     

Die Kristallstruktur von Ammonium-dioxodifluorovanadat

The Crystal Structure of NH₄VO₂F₂ Crystals of NH₄VO₂F₂ are monoclinic, space group Pc, a = 4.814(2), b = 11.434(3), c = 7.214(2) Å, β = 108.84(4)°. Z = 4. The VO₂F-ion is polymeric. The structure consists of endless chains of strongly distorted octahedra with common edges. Two adjacent polyhedra are linked by an asymmetrical oxygen bridge (bond lengths 1.74 and 2.21 Å) and an asymmetrical fluorine bridge (bond lengths 1.97 und 2.21 Å). The terminal V? O- and V? F-distances are 1.55 and 1.86 Å, respectively.     

Die Kristallstruktur von Rb6Si10O23

Zusammenfassung Die Kristallstruktur der Verbindung Rb₆Si₁₀O₂₃ (bisher als Rb₂Si₄O₉ beschrieben) wurde mit Hilfe dreidimensionaler Röntgendaten bestimmt und bis zu einemR-Wert von 0,078 verfeinert. Die Gitterparameter der rhombischen Elementarzelle (C2mm-C _2v ¹⁴ ) betragen:a=9,348,b=16,290 undc=8,055 Å. Die Struktur besitzt ein dreidimensionales Gerüst aus [SiO₄]-Tetraedern, die sowohl über 4 als auch über 3 Ecken vernetzt vorliegen. Die Anordnung der Tetraeder kann aus der Tridymitstruktur abgeleitet werden und zeigt noch deutlich pseudohexagonale Symmetrie. Bei 500 °C geht die Verbindung in eine Hochtemperaturform mit hexagonaler Symmetrie über (a=9,48 undc=8,16 Å bei 500 °C).

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The crystal structure of Rb₆Si₁₀O₂₃

The crystal structure of the compound Rb₆Si₁₀O₂₃ (identical with Rb₂Si₄O₉) has been determined by means of three-dimensional X-ray data resulting anR-value of 0.078. The lattice parameters of the orthorhombic unit cell (C2mm-C _2v ¹⁴ ) are:a=9.348,b=16.290 andc=8.055 Å. The structure consists of a three-dimensional framework built up by [SiO₄] tetrahedra sharing 4 as well as 3 corners. The arrangement of tetrahedra can be derived from tridymite structure and exhibits pseudohexagonal symmetry. The compound transforms to a high-temperature modification with hexagonal symmetry at 500 °C (a=9.48 andc=8.16 Å).

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