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%.     

Untersuchungen an quaternären Fluoriden LiMeIIMeIIIF6 Die Struktur von LiCaAlF6

LiCaAlF₆ crystallizes trigonal (lattice constants a = 4.996, c = 9.636 Å; Z = 2, space group P3 1c) in a structure which is derived from the Li₂ZrF₆ type. Refinement by least squares yielded R = 0.073.     

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.     

Koordinationschemische Untersuchungen an Zinkdialkylen. X. Über die Reaktion von Zinkdimethyl mit sekundären Aminen

Dimethyl zinc reacts with diethyl amine, piperidine and morpholine forming definite 1:2- or 1:1-complexes. The weaker basic secondary amines pyrroline, pyrazolidine and imidazoline cause the evolution of methane and the formation of the corresponding zinc amides. In this way zinc pyrrolide, zinc pyrazolide and zinc imidazolide were obtained in form of pure substances.     

Über die Verbindung Ca4PtO6

During the recovery of Pt from reaction products of the catalytic NH₃ oxidation by CaO filters a compound is formed, which has been described and structurell investigated as Ca₄PtO₆ by CZAYA¹).     

Über die Reaktion einiger 2H-Pyran-2-on-Derivate mit primären Aminen

On the Reaction of Some 2H-Pyran-2-one Derivatives with Primary Amines The versatile reactivity of 6-unsubstituted 2H-pyran-2-ones towards aliphatic and aromatic amines has been studied. It was found that the result of the reaction depends not only on the substitution of 2H-pyran-2-ones and on the structure of amines, but also on the stoichiometric ratio of reacting compounds.     

Über Ligandenumverteilungsreaktionen an ternären Siliciumtetrahalogeniden in Gegenwart von Pyridin

On Ligand-Rearrangement-Reactions at Mixed Silicon Tetrahalides in the Presence of Pyridine The exchange of substituents on mixed silicon tetrahalides completely takes place after few hours in CHCl₃ at 334 K in presence of small quantities of pyridine or pyridinium salts. The exchange equilibria does not deviate much from the values expected from ideal random sorting. Mixed silicon tetrahalides are stable for some days at 298 K in CHCl₃ in presence of pyridine or pyridinium salts respectively, so that by the reaction of binary silicon tetrahalides (SiBr₄, SiI₄) with (pyH)Cl all mixed silicon tetrahalides may be identified side by side. A separation by destillation of the mixtures is impossible because of easy dismutation reactions in presence of pyridine. The influence of pyridine takes place presumable above the formation of addition compounds.     

Über einige Umwandlungsprodukte des «BLIX-Sulfatids» und die Herstellung von quartären Dihydro-sphingosinium-Salzen

In the sulfatide fraction of beef spinal-cord, isolated according to the method of BLIX [9] and LEES [14], there are also sulfatides present derived from 2S, 3R-1, 3-dihydroxy-2-amino-octadecane.     

Über die Aktivierung von Molekeln an oxidischen Halbleiteroberflächen

Assuming inelastic scattering of quasi-free charge carriers of solids by adsorbed gas molecules, a simple model for heterogeneous catalytic reactions is developed which allows to describe mathematically the increase of catalytic activation energy on increasing deviation of the energy of the impact partners from the resonance condition of energy transfer. The model is proved for simple decomposition reactions.     

Struktur und Eigenschaften quaternärer Chalkogenide MIAIIIBIVX. III. Über die Verbindungen AgTiZrTe4 und Ag2TiZrTe4

Structure and Properties of Quaternary Chalcogenides M^IA^IIIB^IVX . III. On the Compounds AgTiZrTe₄ and Ag₂TiZrTe₄ Preparation and properties of the compounds AgTiZrTe₄ and Ag₂TiZrTe₄ are reported. The structure deduced from X-ray diffraction diagrams is closely related to the structure of TiZrTe₄ showing an ordered accomodation of Ti and Zr atoms at the octahedral sites of the CdI₂ type structure. The interlayers free of Ti and Zr atoms are suggested to be in part occupied by Ag⁺ ions in an ordered sequency, which allows to explain the occurrence of 8 Te layers in the repeating unit.     

Über die thermische Trimorphie von KGaCl4

On the Thermal Trimorphism of KGaCl₄ KGaCl₄ exists in three enantiotropic forms: KGaCl₄-I is stable below ?25°C, KGaCl₄-II between ?25 and about 130°C, KGaCl₄-III above 130°C up to the melting point (259°C). KGaCl₄-III belongs to the baryte type of structure, KGaCl₄-II crystallizes with the KAlCl₄-type (distorted baryte). Thermal expansion of both forms (II, III) and the phase transition II ? III are investigated thoroughly.     

Über die elektronenstossinduzierte phenyl-Umlagerung bei 4-Phenyl-chinuclidinen

The mass spectra of 4-phenylquinuclidines are characterised by an easy loss of C₇H₇ from the molecular ion. This unexpected fragmentation process can be explained by phenyl migration prior to fragmentation.     

Über die Magnetischen Eigenschaften der Cobaltate Na6CoS4, Na6CoSe4 und K6CoS4

Magnetic Properties of the Cobaltates Na₆CoS₄, Na₆CoSe₄, and K₆CoS₄ The alkali metal cobalt chalcogenides Na₆CoS₄, Na₆CoSe₄, and K₆CoS₄ crystallize in the space group P6₃mc with Z = 4. The structure is characterized by isolated [CoX₄]-tetrahedra. The magnetic susceptibilities show Curie-Weiss behaviour. The deviations at low temperatures are caused by antiferromagnetic interactions. The magnetic moments are discussed with regard to ligand-field parameters.     

Über quaternäre Oxoplumbate(IV). Zur Kenntnis von Rb3NaPbO4

On Quaternary Oxoplumbates(IV). On Rb₃NaPbO₄ For the first time, Rb₃NaPbO₄ has been prepared by annealing mixtures of Na₂PbO₃ and RbO_0.84 with Rb:Na:Pb = 4:2:1 [nonhermetic Ag-cylinders, sealed under vacuum in Duran-glass ampoule, 480°C, 180 d (single crystals)]. The colourless crystals are of squatted shape. The structure determination [2943 symmetry independent hkl, four-circle-diffractometer PW 1100 (Fa. Philips), ω-2Θ-scan, AgKα, R = 8.64%, R_W = 6.59%, absorption not considered] confirms the space group P2₁/c with a = 1101.79(26), b = 662.66(11), c = 1115.01(30) pm, β 112.027(21)°. The structure is characterized by isolated [PbO₄]-tetrahedra and [Na₂O₆]-tetrahedra-doubletts, C.N. 5 and 7 for Rb⁺. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.     

Über die Chemisorption von Pyridinbasen an Metalldithiophosphinaten

On the Chemisorption of Pyridine Bases on Metal Dithiophosphinates The planar resp. tetrahedral metal dithiophosphinates Nil₂ ( 1 ) resp. CoL₂ ( 2 ) (L = CH₃(p-CH₃OC₆H(₄)P(S)S-) give well defined penta-or hexacoordinated adducts of the types ML₂B or ML₂B₂ with pyridine, methylpyridines or pyridine carboxylic acid esters. Enthalpies of the reaction were calorimetrically determined in some cases and the adsorption of the gaseous bases on solid 1 or 2 investigated by means of gas chromatography. The adsorption process could be satisfactorily described by LANGMUIR 's isotherme and the isosteric enthalpies of adsorption were found to 60–95 kj mol^?1. This and the observed parallelism between the “relative surface density” and the enthalpies of adduct formation as a relative measure for the bond strength M–B led to the conclusion that the bases are chemisorbed via coordinative bonds ever under the conditions of gas chromatography.