Darstellung und Kristallstruktur von ZrP2S6 und ThP2S6

Preparation and Crystal Structure of ZrP₂S₆ and ThP₂S₆ The compounds ZrP₂S₆ ( I ) and ThP₂S₆ ( II ) are synthesized from the elements at 750–800°C. They are isotypic (P4₂/m, Z = 2; I : a = 668.2, c = 948.9 pm; II : a = 688.0, c = 990.3 pm) and to be described as M⁴⁺(P₂S₆)^4?. The thiohypodiphosphate anion has ideal staggered conformation. The cation is coordinated by a (slightly deformed) 42 m dodecahedron of S atoms. The geometrical details correspond to the most favourable ligand distribution.     

Hochdrucksynthese und Struktur von Rb2PtH6 und Cs2PtH6, ternären Hydriden mit K2PtCl6-Struktur

High-pressure Synthesis and Structure of Rb₂PtH₆ and Cs₂PtH₆, Ternary Hydrides with K₂PtCl₆-Structure The ternary platinum hydrides Rb₂PtH₆ and Cs₂PtH₆ were synthesized by the reaction of rubidium hydride and cesium hydride, respectively, with platinum sponge under a hydrogen pressure above 1 500 bar at 500°C. X-ray investigations on powdered samples and elastic neutron diffraction experiments on the deuterated compounds at the time-of-flight spectrometer POLARIS led to their complete structure determination. Their atomic arrangements are isotypic with that of K₂PtCl₆ containing isolated [PtH₆]^2?-octahedra (space group: Fm3 m, Z = 4).     

Synthese und Strukturuntersuchung von CoV2O6

Synthesis and Structure Determination of CoV₂O₆ The hitherto unknown compound CoV₂O₆ was prepared by solid state reaction in single crystal form. The X-ray single crystal investigations lead to the space group C? C2 with a = 9.256, b = 3.508, c = 6.628 Å, β = 111.55°. CoV₂O₆ is isotypic with ZnV₂O₆ or β-CdV₂O₆. It shows an octahedral coordination of Co²⁺ and constructional units like V₂O₅.     

Synthese von 2-Thia-6-aza-adamantan und Derivaten

The synthesis of 2-thia-6-aza-adamantane ( 19 ) and several of its derivatives was achieved starting from 9-azabicyclo[3.3.1]nona-2,6-diene ( 9 ) which was prepared from cis, cis-cycloocta-1, 5-diene ( 1 ). Transannular addition of sulfur dichloride to its N-benzenesulfonyl and N-formyl derivatives 10 and 11 yielded the tricyclic dichlorides 12 and 13 , respectively; the 2-thia-6-aza-adamantanes 14–19 were synthesized from 13 .     

Herstellung und Anionenkonstitution von kristallinen Tetramethylammonium-alumosilicaten und -alumosilicatlösungen

Synthesis and Anion Constitution of Crystalline Tetramethylammonium-aluminosilicates and -aluminosilicate Solutions Crystalline tetramethylammonium aluminosilicates with molar constitutions of wN(CH₃)₄OH · xSiO₂ · y Al₂O₃ · zH₂O and w = 1 to 1.2; x = 1; y = 0.02 to 0.5; z = 8.1 to 9.7 has been obtained from mixtures of diluted TMA aluminate and TMA silicate solutions with different molar Si/Al ratios by concentration and cooling down of the mixtures. Investigations of the TMA aluminosilicates by means of trimethylsilylation method show that the structure of the TMA aluminosilicates consists of double fouring units in analogy to the aluminum free TMA silicates. The arrangement of the Al atoms in the double four-rings agrees in general with Loewenstein's rule and leads to five distinct types of double four-rings with different Al content and Si? Al distribution. By the methods used in this study no distinction can be made between monomeric or polymeric arrangements of the double four-ring units. The existence of aluminosilicate anions in aqueous solutions is discussed.     

Synthese und Kristallstruktur der Hydroxy-lactone von 6-Methyl-2-propionyl- und 3-Methyl-2-propionylbenzoesäure

The isomers 6-methyl-2-propionyl- and 3-methyl-2-propionylbenzoic acid were synthesized and separated by DCC (droplet counter-current) chromatography. The crystal structure analyses showed that these compounds are hydroxylactones in the solid state.     

Röntgenographische Untersuchungen und Strukturchemie von Chalkogenomolybdaten und -wolframaten

X-Ray Investigations and Structure Chemistry of Chalkogenomolybdates and - tungstates. I. Crystallographic data of compounds of the type A₂MeX₄, A₂MeOX₃, and A₂MeO₂X₂ (A = K, NH, Rb, Cs; (Me = Mo, W; X = S, Se) are discussed and general trends are illustrated. The molybdates and tungstates A₂MeX₄ and A₂MeOX₃ (A = K, NH, Rb, Cs; X = S, Se) crystallize in the rhombic space group D? Pnma. The compounds (NH₄)₂MeO₂X₂ (Me = Mo, W; X = S, Se) crystallize in the monoclinic space group C? C2/c.     

Darstellung und Kristallstruktur von K6[Al2O6] und Rb6[Al2O6]

Preparation of Crystal Structure of K₆[Al₂O₆] and Rb₆[Al₂O₆] Colourless single crystals of K₆[Al₂O₆] have been prepared from intimate mixtures of KAlO₂ and K₂O (550°C, 90 d). The structure determination from four-circle diffractometer data (MoKα , 742 I_o(hkl), R = 2.2%, R_w = 2.1%) confirms the space group C2/m with Z = 2; a = 698.25 pm, b = 1 103.54 pm, c = 646.49 pm, β = 102.49°. Colourless single crystals of hitherto unknown Rb₆[Al₂O₆] have been prepared from intimate mixtures of RbAlO₂ and Rb₂O (520°C, 120 d). The structure determination from four-circle diffractometer data (MoKα , 1 240 I_o(hkl)) results in the residual values R = 7.2%, R_w = 4.9%; space group C2/m; a = 725.92 pm, b = 1 143.33 pm, c = 678.06 pm, β = 104.05°; Z = 2. K₆[Al₂O₆] and Rb₆[Al₂O₆] are isostructural with K₆[Fe₂O₆]. A characteristic structure unit is the anion [Al₂O₆]^6? consisting of two edge-sharing [AlO₄] tetrahedra. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), the Madelung Part of Lattice Energy (MAPLE) and the Charge Distribution (CHARDI) are calculated and discussed.     

Löslichkeiten und Aktivitätskoeffizienten von H2S in Elektrolytmischungen

From solubility measurements on hydrogen sulfide in aqueous solutions of the composition [H⁺] = HM, [Na⁺] = (I — H) M = A M, [Cl^?] = I M at 25°C, the molar and molal activity coefficients of H₂S have been calculated. The activity coefficients of H₂S in the electrolyte mixtures have been found to be additive functions of the activity coefficients in the individual electrolyte solutions at the same ionic strength. This result is predicted by the internal pressure theory of salt effects on non-electrolyte activity coefficients, provided that the volume change upon mixing two electrolyte solutions of the same ionic strength is zero.     

Röntgenelektronenspektren und magnetische Momente von Heteropolykomplexen

X-Ray Photoelectron Spectra and Magnetic Moments of Heteropoly Complexes Some isopoly and heteropoly complexes had been prepared and studied by x-ray photoelectron spectroscopy. The bonding energies of the electrons O 1s, Mo 3d, W 4d, and of the hetero element Z 2p were discussed. The results has been compared with magnetic data. Interpretation of ¹H-NMR spectra allowed to explain some features of the nickel compounds which result in higher bonding energies of the Ni 2p electrons.     

Darstellung und eigenschaften von CeTe2O6 und ThTe2O6, verbindungen mit einer neuen überstruktur des fluorit-typs

Preparation and Properties of CeTe₂O and ThTe₂O₆, Compounds with a New Superstructure of the Fluorite Type It is demonstrated that in the systems MO₂/TeO₂ (with M = Ce, Th), treated in air and at 600°C, only phases of composition MTe₂O₆ are formed. They pertains to the cubic crystal system and constitutes a new type of fluorite-superstructure. Different aspects of its crystal chemistry are commented and also the infrared spectra are recorded and briefly discussed.