Über Alkalimetallmanganchalkogenide A2MnX2 mit A K,Rb oder Cs und X S,Se oder Te

Inhaltsübersicht. Die Verbindungen K₂MnS₂, Rb₂MnS₂, Cs₂MnS₂, K₂MnSe₂, Rb₂MnSe₂, Cs₂MnSe₂, K₂MnTe₂, Rb₂MnTe₂ und Cs₂MnTe₂ wurden durch Umsetzungen von Alkalimetall-carbonaten mit Mangan bzw. Mangantellurid in einem mit Chalkogen beladenen Wasserstoffstrom erhalten. Kristallstrukturuntersuchungen an Einkristallen ergaben, daß alle neun Verbindungen isotyp kristallisieren (K₂ZnO₂-Typ, Raumgruppe Ibam). Untersuchungen zum magnetischen Verhalten zeigen antiferromagnetische Kopplungen der Manganionen in den [MnX_4/2^2–]-Ketten, On Alkali Metal Manganese Chalcogenides A₂MnX₂ with A K, Rb, or Cs and X S, Se, or Te The compounds K₂MnS₂, Rb₂MnS₂, Cs₂MnS₂, K₂MnSe₂, Rb₂MnSe₂, Cs₂MnSe₂, K₂MnTe₂, Rb₂MnTe₂, and Cs₂MnTe₂ were synthesized by the reaction of alkali metal carbonates with Mn or MnTe in a stream of hydrogen charged with chalcogen. Structural investigations on single crystals show that all nine compounds crystallize in isotypic atomic arrangements (K₂ZnO₂ type, space group Ibam). The magnetic behaviour indicates antiferromagnetic interactions of the manganese ions within the [MnX_1/2^2–] chains.     

Darstellung und Struktur von BaAl2Se4, BaGa2Se4, CaGa2Se4 und Caln2Te4

Preparation and Crystal Structure of BaAl₂Se₄, BaGa₂Se₄, CaGa₂Se₄, and CaIn₂Te₄ The new compounds BaAl₂Se₄, BaGa₂Se₄, CaGa₂Se₄ and CaIn₃Te₄ crystallize with constants see “Inhaltsübersicht”. The structures are strongly related to the TlSe structure.     

Darstellung,Struktur und magnetische Eigenschaften der Natriumeisenchalkogenide Na6FeS4 und Na6FeSe4

Synthesis, Structure, and Magnetic Properties of the Sodium Iron Chalcogenides Na₆FeS₄ and Na₆FeSe₄ The compounds Na₆FeS₄ and Na₆FeSe₄ have been synthesized by fusion reactions of sodium carbonate with iron and chalcogen in a stream of hydrogen. Structural investigations on single crystals show that both compounds crystallize in an atomic arrangement isotypic with Na₆ZnO₄ (space group P6₃mc). The structure is characterized by isolated [FeX₄]-tetrahedra. The magnetic susceptibilities show Curie-Weiss behaviour. The deviations at low temperatures are obviously caused by antiferromagnetic interactions.     

Über Thio-, Selenido- und Telluridogermanate (III): Zur Kenntnis von K6Ge2S6, K6Ge2Se6 und Na6Ge2Te6

On Thio-, Selenido-, and Telluridogermanates (III): K₆Ge₂S₆, K₆Ge₂Se₆, and Na₆Ge₂Te₆ The new compounds K₆Ge₂S₆ and K₆Ge₂Se₆ crystallize in the monoclinic system, space group C2/m (No 12); lattice constants see “Inhaltsübersicht”. The compounds are isotypic and form the K₆Si₂Te₆ structure. Na₆Ge₂Te₆ crystallizes in the K₆Sn₂Te₆ structure, monoclinic, space group P2₁/c (No 14); lattice constants see “Inhaltsübersicht”.     

Darstellung,Kristallstruktur und spektroskopische Charakterisierung von P4O6Se3

Synthesis, Crystal Structure, and Spectroscopic Characterization of P₄O₆Se₃ P₄O₆Se₃ has been prepared for the first time as a pure substance by photochemical selenation of P₄O₆ with red selenium. The compound crystallizes in a monoclinic system with space group P2₁/a (a = 973.6(2); b = 846.9(2); c = 1277.7(3) pm; β = 90.56(2)°; Z = 4; 1358 diffractometer data; R₁ = 0.044; wR² = 0.099). Bond lengths and angles within the molecule as well as the arrangement of the molecules within the crystal are discussed; vibrational (IR and Raman) and ³¹P-n.m.r. (solution) data are given.     

Nitrido-Sodalithe. III [1]. Synthese,Struktur und Eigenschaften von Zn8[P12N24]X2 mit X = O,S, Se,Te

Nitrido-Sodalites. III. Synthesis, Crystal Structure, and Properties of Zn₈[P₁₂N₂₄]X₂ with X = O, S, Se, Te The P? N-sodalites Zn₈[P₁₂N₂₄]X₂ with X = O, S, Se, Te are obtained by the reaction of HPN₂ with the corresponding zinc chalcogenide ZnX at 750°C. They crystallize in a filled up variant of Zn₇[P₁₂N₂₄]Cl₂ and are isotypic to Zn₈[B₁₂O₂₄]O₂ (I4 3m, a = 823 to 830 pm, Z = 1). The P? N-sodalites contain in the center of their β-cages XZn₄⁶⁺ units which can be described as sections of II/VI-semiconductors. The UV/Vis-spectra of the compounds show in comparison with binary bulk zinc chalcogenides a blue shift of the absorption edge according to the size quantization effect.     

Darstellung und Struktur von Li5Ga4

Preparation and Crystal Structure of Li₅Ga₄ Li₅Ga₄ has been established as further, hitherto unknown phase in the LiGa system. The new compound crystallizes in the trigonal system (P3 m1—D_3d³) with a = 437.5 ± 0.2 pm, c = 825.7 ± 0.2 pm, c/a = 1.885. The structure is strongly related to those of LiGa and Li₃Ga₂.     

Darstellung,Struktur und thermisches Verhalten einer neuen hexagonalen Ge-W-Bronze

Preparation, Structure, and Thermal Behaviour of a New Ge? W Bronce A hexagonal Ge-tungsten bronce with the composition Ge_0.24 WO₃ is obtained by chemical vapour deposition of a mixture of GeO₂ and WO₂(temperature gradient: 930 to 830°C). By means of an X-ray crystal structure analysis the space group was determined to be P622 and the lattice constants a = 744.0 pm, c = 381.7 pm. In absence of oxygen Ge_0.24 WO₃ is stable up to 850°C; in contact with air it is oxydized at temperatures T > 670°C. An anomaly in the thermal lattice expansion at temperatures T > 260°C is discussed.     

Darstellung und Kristallstruktur von SnTl4Se3 mit einer Anmerkung zu TlSe

Preparation and Crystal Structure of SnTl₄Se₃ with a Note on TlSe We describe the preparation and crystal structure of SnTl₄Se₃. It crystallizes as a low symmetric distorted derivative with the In₅Bi₃ type of structure, which itself should be considered as a subfamily of the Cr₅B₃ type of structure: a = 852.2(2) pm, c = 1 272.2(6) pm, c/a = 1.49, Z = 4. Short Sn? Se distances of 311 pm, and 326 pm, respectively, are obtained in [SnSe_2/2] chains running along [001]. Furthermore, short Tl? Se distances are found in quasimolecular bent moieties Tl₂Se: 300 pm, 313 pm, and 347 pm, respectively. SnTl₄Se₃ is a semiconductor. The conductivity of some closely related phases are also reported. Finally, the structure of the well known compound TlSe has been refined for the first time, in order to get some more information about Tl¹⁺? Se distances for square-antiprismatic coordinated Tl¹⁺ ions.     

Komplexe mit aromatischen Carbonsäuren. I Darstellung und Struktur von Zinkpyromellitat-Heptahydrat

Complexes with Aromatic Carboxylic Acids. I. Synthesis and Crystal Structure of Zinc Pyromellitate Heptahydrate The crystal structure of zinc pyromellitate heptahydrate comprises features of ion exchangers, layer-like, and zeolitic structures. Single crystals of this compound were obtained by crystallization in aqueous silicagel. According to the structural properties Zn(H₂O)₅[ZnC₆H₂(COO)₄]·2H₂O is an appropriate formula. Zn(1) is coordinated tetrahedrally by four oxygen atoms of the carboxylate groups. Thus forming folded [ZnC₆H₂(COO)₄] layers to which Zn(2) is bound by only one carboxylate oxygen atom. The coordination sphere of Zn(2) is completed by five water molecules to yield a slightly distorted octahedron. Additional water is accomodated between the layers. The [ZnC₆H₂(COO)₄] layers possess channel-like cavities extending along [100] which are filled by water molecules. Hydrogen bonding is an important feature of this crystal structure.     

K2Ag4Se3, Darstellung und kristallstruktur

By the reaction of potassium carbonate with silver and selenium at 1000 °C, we obtained the ternary compound K₂Ag₄Se₃. Single-crystal investigations revealed the monoclinic space group C2/m; the cell constants are a = 1777.0(10)pm, b = 444.7(3)pm, c = 1185.6(3)pm and β = 108.4(1)°. The atomic arrangement is isotypic with that of K₂Ag₄S₃. The shortest distances between the silver atoms are only a little larger than those in the structure of the element and their geometrical arrangement shows a slightly distorted fragment framework of the f.c.c. lattice.     

Darstellung und Kristallstruktur von CsSb2Se4

Preparation and Crystal Structure of CsSb₂Se₄ CsSb₂Se₄ was prepared by hydrothermal reaction of Cs₂CO₃ with Sb₂Se₃ at a temperature of 115°C. An X-ray structural analysis demonstrated that the compound contains polyselenoantimonate(III) anions (Sb₂Se₄^?)_n, which display both (Sb)Se? Sb and (Sb)Se? Se(Sb) bridges. A ψ-tetrahedral coordination is observed for one of the independent Sb atoms, a ψ-trigonal bipyramidal coordination for the other. The Sb? Se polyhedra are linked through joint corners and edges and in addition via direct Se? Se bonds into sheets.     

Selenostannate aus wäßriger Lösung Darstellung und Struktur von Na4Sn2Se6 · 13 H2O

Selenostannates from Aqueous Solution, Preparation and Structure of Na₄Sn₂Se₆ · 13 H₂O The dimeric anion Sn₂Se₆^4? is prepared by reaction of SnSe₂ with alkali metal selenide in a 1:1 molar ratio. The orange-red hydrated sodium salt Na₄Sn₂Se₆ · 13 H₂O is characterized by a complete X-ray structure analysis and by its vibrational spectrum. The compound is triclinic (P1 ) with a = 7.106(2), b = 10.330(2), c = 19.009(4) Å, α = 78.60(2), β = 85.66(2), γ = 72.85(2)° (?130°C), Z = 2. It contains isolated Sn₂Se₆^4? anions consisting of two edge-sharing tetrahedra [Sn? Se 2.456(1)–2.589(1) Å] which are in contact to the hydrated Na⁺ ions within an extensive hydrogen bridge system. Raman-active vibrations are observed at 260, 202, 188, 116, 93, and 78 cm^?1.     

Darstellung,Struktur und Eigenschaften von Ag10Si3S11

Preparation, Crystal Structure and Properties of Ag₁₀Si₃S₁₁ The novel orange-red thiosilicate Ag₁₀Si₃S₁₁ is formed besides Ag₈SiS₆ by the high - temperature reaction between Ag₂S, Si and S. The single crystal structure analysis shows the compound to be silver orthothiosilicate thiodisilicate-(1:1) Ag₁₀(SiS₄)(Si₂S₇). The mean Si? S bond lengths are 2.137 Å for SiS₄^(4?) and 2.129 Å for the hitherto unknown Si₂S₇^(6?). The cation sublattice is slightly imperfect. inferring a certain mobility of the Ag⁺ ions. Ag₁₀Si₃S₁₁ crystallizes in the triclinic space group P1 . Lattice constants see ?Inhaltsübersicht”?. The vibrational spectrum (IR) shows absorptions within the characteristic spectral regions for asymmetric and symmetric stretching vibrations of the SiS₄ tetrahedra at 490–515 and 423–433 cm^?1.     

Darstellung und Charakterisierung von Wolframkomplexen mit ER−-Liganden; E = O,S, Se,Te; R = Alkyl,Aryl

Synthesis and Characterization of Tungsten Complexes with ER^?-Ligands, E = O, S, Se, Te; R = Alkyl, Aryl The reaction of η⁷-C₇H₇W(CO)₂I with ER^? bases yielded several types of compounds, η⁷-C₇H₇W(CO)₂ER, η³-C₇H₇(CO)₂W(μ-OR)₃W(CO)₂-η⁴-C₇H₈, (CO)₄W(μ-ER)₂W(CO)₄, η⁷-C₇H₇W(μ-ER)₃W(CO)₃ and η⁷-C₇H₇W(μ-ER)₃W(CO)(μ-ER)₂W(CO)₄. The compounds were characterized by elementary analysis and their spectroscopie data. The structures of typical representatives of every class of compounds were confirmed by X-ray structure analysis.     

Selenogermanate aus wäßriger Lösung: Darstellung und Struktur von Na4Ge2Se6 · 16 H2O

Selenogermanates from Aqueous Solution: Preparation and Structure of Na₄Ge₂Se₆ · 16 H₂O Selenogermanates(IV) are prepared from aqueous solutions by reaction of alkali selenides with GeSe₂. Na₄Ge₂Se₆ · 16 H₂O, being obtained from stoichiometric 1:1 quantities, is characterized by a complete X-ray structure analysis and by vibrational spectra. The compound is monoclinic (P2₁/c) with a = 9.894(4), b = 11.781(5), c = 12.225(6) Å, β = 92.90(4)°, Z = 2. It contains isolated Ge₂Se₆^4? anions consisting of two edge-sharing tetrahedra [Ge? Se 2.303(2)–2.419(2) Å] which are in contact to the hydrated octahedral [Na(H₂O)₆]⁺ ions through Se ? H? O bridges within an extensive hydrogen bridge system. Raman-active vibrations are observed at 306, 294, 207, 139, and 121 cm^?1. Adamantane-like Ge₄Se₁₀^4? can be prepared in a similar way as Ge₂Se₆^4? if a 1:2 molar ratio of alkali selenide to GeSe₂ is employed.     

Synthese,Struktur und dynamisches Verhalten von Cyclopentadienylboranen

The cyclopentadienylboranes I–XI have been synthesized by the reaction of halogenoboranes with cyclopentadienyl-trimethylsilanes, -trimethylstannanes and -lithium compounds. Substitution reactions at the boron atom in III and VIII with tetramethylstannane and dimethylamine lead to the cyclopentadienylboranes XII–XV. The structures of I–XV have been investigated by ¹H-, ¹³C- and ¹¹B-n.m.r. measurements. The 5-trimethylsilyl-cyclopentadienylboranes show a dynamic behaviour due to sigmatropic rearrangements. The influence of a boryl ligand on the speed of these rearrangements is discussed.     

Darstellung und Struktur von K3(SH)TeS3

Preparation and Crystal Structure of K₃(SH)TeS₃ K₃(SH)TeS₃ has been prepared and structurally characterized. It crystallizes cubic with a = 1270(2) pm, space group 143m. The SH- Ions are surrounded by an octahedron of K⁺ ions. The TeS₃^2?. anions form flat trigonal pyramids with Te? S distances of 234.8(2) pm.