Zur Kenntnis von RbTaO3 – ein neuer Typ einer Schichtstruktur

On the Knowledge of RbTaO₃ – a New Type of a Layer Structure RbTaO₃ crystallizes monoclinic with a = 9.58₉, b = 8.50₅, c = 8.13₅ Å, β = 94.8₇°, Z = 8, space group C2/m. The crystal structure (Fourcircle-diffractometer data, 4° ≤ Θ ≤ 33°, 1014 hkl, MoKα, R = 9,9%) shows sheets [TaO₃] connected by Rb; one half of Ta is surrounded by O octahedrally, the other part tetragonal-pyramidal. Effective Coordination Numbers, ECoN, and the Madelung Part of Lattice Energy, MAPLE, have been calculated and are discussed.     

LiDy2Cl5, ein Zwischenprodukt bei der „metallothermischen”︁ Reduktion von DyCl3 mit Lithium

LiDy₂Cl₅, an Intermediate of the Metallothermic Reduction of DyCl₃ with Lithium LiDy₂Cl₅ has been obtained via 2 Li + 2 DyCl₃ = LiDy₂Cl₅ + LiCl as black single crystals (700°C, 1 week, sealed tantalum container) and crystallizes monoclinic with a = 1545.6(7), b = 659.2(2), c = 728.7(3) pm, β = 95.79(3)°, Z = 4, C2/c. Octahedra [LiCl₆] are connected via common corners to rings [Li₄Cl₂₀], these parallel (100) to layers [LiCl₄]. Bicapped trigonal prisms [DyCl₈] are connected to a three-dimensional network [(DyCl1_3/3Cl2_3/3Cl3_2/4)] ? [Dy₂Cl₅].     

Über die Cycloaddition von Dithiocyan und Trithiocyan mit Hexafluoraceton und Folgeprodukte aus der Spaltung der Schwefel-Schwefel-Bindung mit elementarem Chlor im Dithiocyan-Hexafluoraceton-Addukt

Cycloaddition of Dithiocyanogen and Trithiocyanogen with Hexafluoroacetone and Products of the Cleavage of the Sulfur-Sulfur Bond in Dithiocyan-Hexafluoroacetone Adduct by Elemental Chlorine The reaction of dithiocyanogen and trithiocyanogen with hexafluoroacetone (HFA) leads to the cycloaddition products (SCN)₂ · 4 HFA 1 and S(SCN)₂ · 4 HFA 2 . These are the first reactions of (SCN)₂ and S(SCN)₂ without cleavage of the S—S bonds. Elemental chlorine cleaves in 1 the S? S bond and 3 is formed. In 3 the chlorine atom can be replaced by the rests —CN 4 , (C₆H₁₁)₂N— 5 , and n-C₄H₉– 6. 6 eliminates one molecule of HFA by warming up and the four-membered ring 7 is formed. The compounds were characterized on the basis of mass and nmr spectra.