Kationenverteilung und Überstrukturordnung in ternären und quaternären Sulfidspinellen MIIMS4 – Einkristallstrukturuntersuchungen

Cation Distribution and Superstructure Ordering in Ternary and Quaternary Sulfide Spinels M^IIM₂^III S₄ – Single Crystal Structure Determinations The crystal structures of spinel type MIn₂S₄ (M ? Mn, Co, Ni), MCr_2?2xIn_2xS₄ (M ? Mn, Ni), and Cd_0.52Co_0,48Cr₂S₄ were reinvestigated by X-ray methods using single crystals grown by vapour phase transport technique. The indium sulfides possess a partially inverse distribution of the metal ions on the tetrahedral (8a) and octahedral sites (16d) of the structure. The degrees of inversion λ are 0.34 (MnIn₂S₄, a = 1072.0(1) pm, structural parameter u = 0.25726(2)), 0.84 (CoIn₂S₄, a = 1058.1(1) pm, u = 0.26921(5)) und 0.93 (NiIn₂S₄ a = 1050.5(1), u = 0.26040(3)). In the case of the chromium indium sulfide solid solutions, the degrees of inversion (and the structural parameters) increase (and decrease) linearly with increase in indium content x. ψ-scans of reflections not allowed in the space group Fd3 m do not prove simultaneous diffraction. Refinement of the structure of MnIn₂S₄ in space group F4 3m results in a partial superstructure ordering of Mn and In on the tetrahedral sites, 4a Mn_0.83In_0.17, 4c Mn_0.49In_0.51. In the case of Cd_0.52Co_0.48Cr₂S₄, superstructure ordering is like Cd_0.41Co_0.59 and Cd_0.62Co_0.38, respectively.     

Organische Phosphorverbindungen XXV Darstellung und Eigenschaften von sekundären und tertiären Phosphinsulfiden

Two new processes for the preparation of sec. phosphine sulfides which involve reaction of dialkylamino-dialkyl or diaryl phosphines with hydrogen sulfide, and of dialkylthionophosphonates, (RO)₂P(S)H, with GRIGNARD or organolithium reagents, respectively, are described. The addition of sec. phosphine sulfides to olefins and the condensation of sec. phosphine sulfides with N-hydroxymethyldialkylamines are reported. The conversion of tert. Phosphine sulfides to the corresponding tert. phosphine oxides is readily achieved with hydrogen peroxyde. The physical properties of several new unsymmetrical tert. phosphine sulfide and oxides are listed.     

Massenspektren von sekundären Vinylcarbinolen

The mass spectra of secondary vinylcarbinols of the structure R? CH(OH)? CH?CH₂ show the same fragments as those of the isomeric ethylketones R? CO? C₂H₅. This is the result of a rearrangement of the molecular ions of the vinylcarbinols to molecular ions of the ethylketones before fragmentation occurs. Compounds of the two classes differ only slightly from one another in the intensity values.     

Cs2[MnSnTe4]: Ungewöhnliche Synthese einer quaternären Phase mit eindimensionalen,ternären Anionensträngen

Cs₂[MnSnTe₄]: Uncommon Synthesis of a Quaternary Phase Based on One‐dimensional, Ternary Anionic Chains Reaction of a methanol solvate of yet not reported ortho‐tellurostannate(IV) salt Cs₄[SnTe₄] ( 1 ) with MnCl₂·4H₂O in aqueous solution led to the formation of the novel compound Cs₂[MnSnTe₄] ( 2 ), the crystal structures of which was determined by means of single crystal X‐ray diffraction. 2 crystallizes in the space group Fddd. Lattice dimensions at 203 K: a = 681.9(1), b = 1506.3(3), c = 2596.7(5) pm, V = 2667.2(9)·10⁶pm³; R₁ = 0.0655. By synthesis of 2 , transfer of complete ortho‐tellurostannate anions into the coordination sphere of a 3d‐transition metal atom succeeded for the first time. The structure of 2 is based on a ternary anionic substructure formed by one‐dimensional, parallel ¹{[MnSnTe₄]^2—} strands. In spite of the preparation in solution, 2 does not provide any solvent molecules in the crystal lattice.     

Neue Untersuchungen an quaternären Fluoriden

New Investigations on Quaternary Fluorides For the first time the quaternary fluorides M¹₂M^IILnF₇ (M¹ = Na, Ag; M^II = Ca, Cd; Ln = Er? Lu) had been prepared and examined with with X-ray diffraction. All these compounds crystallize in a cubic face-centered lattice. Colourless single crystals of Na₂CdYbF₇ were obtained and the structure was determined. Na₂CdYbF₇ crystallizes in the space group Fm3M-O⁵_h, No. 225. The single-crystal diffraction data refer to a Defect-Fluorite-Structure. The R-value for 332 observed (29 independend) reflections is 2.2%.