Die Kristallstruktur von W2CoB2 und isotypen Phasen

Zusammenfassung Die Phasen Mo₂CoB₂, Mo₂NiB₂, W₂FeB₂, W₂CoB₂ und W₂NiB₂ kristallisieren in einem neuen Typ (W₂CoB₂-Struktur). Die Zelle ist orthorhombisch, die Raumgruppe D _2h ²⁵ -I mmm. Die Punktlagen sind 4 W in 4 f), 2 Co in 2 a) und 4 B in 4 h). Die strukturellen Bauelemente werden mit jenen von Mo₂FeB₂ (U₃Si₂-Typ) verglichen.

---

The ternary compounds Mo₂CoB₂, Mo₂NiB₂, W₂FeB₂, W₂CoB₂ and W₂NiB₂ crystallize with a new type (W₂CoB₂-structure). The elementary cell is orthorhombic, the space group being D _2h ²⁵ -I mmmm. The atomic positions are determined to be 4 W in 4 f), 2 Co in 2 a) and 4 B in 4 h). Both crystal structures W₂CoB₂ and Mo₂FeB₂ (U₃Si₂-type) are compared with respect to the trigonal prismatic surrounding of the boron atoms.

---

---

Mit 1 Abbildung     

Die Kristallstruktur von V3Al und sein Mischungsverhalten mit isotypen Phasen

Zusammenfassung Im Bereich der homogenen Mischphase V_1,00–0,47Al_0,00–0,53 wird die metastabile Kristallart V₃Al erfaßt. V₃Al besitzt Cr₃O-Struktur (-Wolfram-Typ). Lückenlose Mischreihen von V₃Al mit V₃Sb und Nb₃Sn werden nachgewiesen. Unter gleichen Bedingungen, Homogenisierung bei 1000 und 1100°C, treten dagegen mit V₃Si, V₃Ge und Nb₃Al Mischungslücken auf.Mit 1 Abbildung     

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.

---

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.

---

---

Mit 4 Abbildungen     

Die Kristallstruktur des Ta6Cu8Be15 und verwandter Phasen

Ohne Zusammenfassung     

Darstellung und Kristallstruktur der Phasen Zr3S4 und Hf3S4

The crystal structure of the Zr₃S₄ phase was confirmed by single crystal work. The structure parameters were refined. An isotypic phase forming a microcrystalline powder could be prepared in the system hafnium/sulphur.     

Synthese,Kristallstruktur und elektronische Bandstruktur der isotypen Sulfidchloride CuBiSCl2 und AgBiSCl2

Synthesis, Crystal Structure and Electronic Band Structure of the Isostructural Sulfide Chlorides CuBiSCl₂ and AgBiSCl₂ Black, platelet crystals of MBiSCl₂ (M = Cu, Ag) were synthesized by heating stoichiometric amounts of MCl and BiSCl. X‐ray diffraction on powders and single‐crystals revealed that the compounds crystallize isostructural with space group Cmcm (Cu/Ag: a = 396.9(1)/397.1(1); b = 1278.6(3)/1371.2(3); c = 859.7(2)/882.4(2) pm). In the crystal structures the Bi^III cations have a bi‐capped trigonal prismatic coordination of two sulfide and six chloride ions. The polyhedra constitute layers equation/tex2gif-stack-2.gif[BiS_2/2Cl_6/3^—] by sharing common edges and faces. The layers are separated by transition metal cations M^I. Their distorted octahedral coordination comprises two short bonds M—S in trans position and four M—Cl bonds that are about 50 pm longer. From relativistic band structure calculations (DFT) is deduced that AgBiSCl₂ is an indirect semi‐conductor with a band gap of about 1.0 eV.     

Darstellung und Kristallstruktur der isotypen Verbindungen Ca2Os3B5 und Eu2Os3B5

Preparation and Crystal Structure of the Isotypic Compounds Ca₂Os₃B₅ and Eu₂Os₃B₅ The isotypic borides Ca₂Os₃B₅ and Eu₂Os₃B₅ crystallizing in the monoclinic space group C2 with Z = 2 were prepared by reaction of the elemental components in sealed tantalum tubes (lattice constants see Inhaltsübersicht). The structure contains puckered osmium-boron layers connected by boron atoms with very short Os? B distances.     

Die Kristallstruktur des Komplexnitrides Mo(Ta,Mo)2N2

In the ternary system Ta/Mo/N a complex nitride of formula Mo(Ta,Mo)₂N₂ was observed at a nitrogen pressure of 360 bar and a temperature of 1,600°C. The crystal structure was determined from X-ray powder diagrams. The tetragonal unit cell, space groupI4/mmm-D _4h ¹⁷ , lattice parametersa=0.3051 nm,c=1.2530 nm contains ten atoms with an arrangement of the metal atoms corresponding to the MoSi₂-Type structure.

     

Dimethylzinndithioquadratat: Die Kristallstruktur des Benzol-Solvats und des Dimethylsulfoxid-Addukts

Dimethyltin Dithiosquarate: The Crystal Structure of the Benzene Solvate and of the Dimethylsulfoxide Adduct (CH₃)₂SnS₂C₄O₂ · 1/3 C₆H₆ ( I ) crystallizes in the orthorhombic space group Pnma. a = 14.393(2), b = 21.668(3), c = 10.424(1) Å, Z = 12. (CH₃)₂SnS₂C₄O₂ · (CH₃)₂SO ( II ) is monoclinic, space group P2₁/n, a = 9.918(5), b = 12.028(6), c = 12.223(6) Å, β = 108.82(3)°, Z = 4. In I there are two independent dimethyltin dithiosquarate molecules. But in both molecules the Sn atoms display weak coordinative bonds to two O atoms of adjacent dithiosquarate groups. The distances amount 2.873 Å (2×), resp. 2.678 and 2.831 Å. The coordination number of tin becomes 6 and the structure gets connected in three dimensions. In II dimethylsulfoxide is bound with the O atom to Sn (2.345 Å) and the result is a distorted trigonal bipyramid. There a more distant O atom (2.944 Å) leads to a connection of the molecules to a ribbon. The changes of the geometrical parameters are described, which result from the progressive approach of the one O atom.     

Die Kristallstruktur der isotypen Verbindungen KAg(NO3)2, NH4Ag(NO3)2 und RbAg(NO3)2

KAg(NO₃)₂ crystallizes in space group P2₁/a-C _2h ⁵ ,a=13.953,b=4.955,c=8.220 Å, =97.76°,Z=4. X-ray intensities were collected with a two-circle diffractometer. The structure was solved by means of direct methods andFourier syntheses and was refined by the least squares method toR=0.034 with 1346 observed reflexions. ¹ {Ag₂(NO₃)₄}^2–-chains run parallel toy and are linked by potassium ions. Ag shows a distorted tetrahedral coordination with four relatively close O. K is irregularily surrounded by ten O. The isotypic compounds NH₄Ag(NO₃)₂ and RbAg(NO₃)₂ were refined toR=0.032 and 0.035, respectively. The coordination figures are compareable with those in KAg(NO₃)₂.

     

Darstellung und Kristallstruktur der bekannten Zintl‐Phasen Cs3Sb7 und Cs4Sb2

Synthesis and Crystal Structure of the known Zintl Phases Cs₃Sb₇ and Cs₄Sb₂ Cs₃Sb₇ and Cs₄Sb₂ were synthesized from the elements and their crystal structures were determined on the basis of single crystal x‐ray data. Cs₃Sb₇ crystallizes in the monoclinic system with space group P2₁/c (a = 1605.7(1) pm, b = 1571.1(1) pm, c = 2793.9(2) pm, β = 96.300(2)°, Z = 16) and contains anions Sb₇^3–. In the structure of Cs₄Sb₂ (orthorhombic, space group Pnma, a = 1598.5(3) pm, b = 631.9(2) pm, c = 1099.5(2) pm, Z = 4) dumbbells Sb₂^4– are present.     

Die Kristallstruktur der Verbindungen BaCaGaF7 und BaCaCrF7

Crystal Structure of the Compounds BaCaGaF₇ and BaCaCrF₇ The isostructural fluorides BaCaGaF₇ and BaCaCrF₇ (values in parentheses) crystallize monoclinically in space group P2/n, Z = 4: a = 539.0 (539.8), b = 541.0 (542.2), c = 1897.8 (1900.6) pm, β = 92.33 (92.10)°. Complete X-ray single crystal structure determinations showed, that the compounds are built up from triple layers [CaF_8/2 · MF₃]^2?, which consist of a central sheet of edge-sharing CaF_8/2^2? polyhedra (distorted square antiprisms) with M^IIIF₆octahedra condensed on it at both sides and which are held together by 12-coordinated barium ions. The resulting average distances are: Ga? F = 187.8 (Cr? F = 189.4) pm, Ca ? F = 236.2 (236.2) pm, Ba? F = 289.4 (289.4) pm. Some relations to the structures of other fluorides are discussed.     

Die Kristallstruktur des Chromarsenids Cr4As3

The crystal structure of Cr₄As₃ has been determined by single crystal photographs: $$\begin{gathered} space group Cm - C_s ^3 \hfill \\ \alpha = 13.16_8 {\AA} \hfill \\ b = 3.54_2 {\AA} \hfill \\ c = 9.30_2 {\AA} \hfill \\ \beta = 102.1_9 \circ \hfill \\ \end{gathered}$$ Cr₄As₃ crystallizes with a novel structure type, which can be derived from the MnP-structure type.     

Synthese und Kristallstruktur der molekularen Clusterverbindung W6Br14

Synthesis and Crystal Structure of the Molecular Cluster Compound W₆Br₁₄ Brownish-black crystals of W₆Br₁₄ are formed in the direct synthesis from W₆Br₁₂ and Br₂ (400 K). The compound crystallizes cubically with neutral cluster molecules ([W₆Br]Br): a = 13.458 Å; Pn3 (Nr. 201); d?(W? W) = 2.653 Å; d?(W? Brⁱ) = 2.616 Å; d?(W? Br^a) = 2.569 Å. The W atoms are 0.03 Å outside of the Br cube faces. The molecules are arranged according to a cF point configuration, but each is rotated ?23° about a threefold axis in order to avoid short inter cluster distances Br^a? Br^a. Nevertheless, via 12 short intermolecular distances per cluster of about d(Brⁱ …? Br^a) = 3.487 Å the clusters are interconnected by forming two independent and interpenetrating 3D nets (Cu₂O type). Although local distortion of the M₆X cluster does not occur, as is expected for this system with 22 electrons per M₆ octahedron, it is assumed that the Jahn-Teller theorem is fulfilled collectively via the low-symmetry nets of intermolecular interactions.     

Die Kristallstruktur von ThGa2 und RuIn3

Zusammenfassung Im System: Th-Ga wird die Phase ThGa₂ mit -ThSi₂-Typ aufgefunden, im System: Ru-In werden die Phasen RuIn₃ mit CoGa₃-Struktur sowie eine Ru-reiche Phase mit hexagonal dichter Packung machgewiesen.Herrn Professor Dr.Erich Hayek zum 60. Geburtstag.     

Die Kristallstruktur der Verbindung SbCl2F3

SbCl₂F₃ crystallizes in the monoclinic space group P 2₁/n (lattice parameters see above). The crystal structure has been determined by PATTERSON methods and refined three-dimensionally by the method of least squares. The structure is ionic and consists of tetrahedral SbCl cations and anions. In these anions pair of octahedrally coordinated Sb-atoms are linked by a fluorine bridge. A new interpretation of the IR and RAMAN spectra and a discussion of the character of the bonds of the fluorine atoms are given.     

Verfeinerung der Kristallstruktur des Natriummetagermanats,Na2GeO3

Zusammenfassung Die Kristallstruktur des Natriummetagermanats, Na₂GeO₃, wurde mit dreidimensionalen Daten bis zu einemR-Wert von 4.4% verfeinert. Daraus ergab sich für die Metagermanatkette ein mittlerer Ge–O-Abstand von 1.836 Å für das Brückensauerstoffatom und von 1.713 Å für das terminale Sauerstoffatom. Der mittlere Na–O-Abstand beträgt 2.39 Å (KZ=5).

---

Refinement of the crystal structure of sodium metagermanate, Na₂GeO₃

The crystal structure of sodium metagermanate, Na₂GeO₃, has been refined by three-dimensional data resulting anR-value of 4.4%. The mean Ge–O distances in the metagermanate chain were found to be 1.836 Å for the bridging oxygen atom and 1.713 Å for the terminal oxygen atom. An average value of 2.39 Å was calculated for the Na–O distance (c.n.=5).

---

---

Mit 1 Abbildung     

Die Kristallstruktur des Bleimonohydrogentriphosphats,Pb2HP3O10

Crystal Structure of Lead Monohydrogentriphosphate, Pb₂HP₃O₁₀ By heating of Pb₂P₄O₁₂ · 2 H₂O at 150°C crystalline Pb₂HP₃O₁₀ is formed topotactically. In these crystals amorphous H₃PO₄ is included. The monoclinic crystals are fourfold twinned. Space group: Cm; unit cell: a = 6.93 ± 0.01, b = 14.34 ± 0.01, c = 5.97 ± 0.01 Å, β = 135.1 ± 0.1°. The crystal structure was determined by heavy-atom method and refined by least-squares calculations. The P₃O₁₀^5? anion consists of three PO₄ tetrahedra connected by common oxygen atoms. The chain has mirror symmetry across a plane passing the middle P atom. Lead is coordinated by eight oxygen atoms. The polyhedra of Pb are connected parallel y and z by common edges. Six P₃O₁₀^5? chains are joined by one lead ion.