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  • 1
    Electronic Resource
    Electronic Resource
    The 7.25-hydrate oftert-butylamine. A semi-clathrate and complex variant of the cubic 12 Å structure type (1995)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 22 (1995), S. 145-154 
    Details
    ISSN: 1573-1111
    Keywords: tert-Butylamine 7.25 H2O ; amine hydrate ; semi-clathrate ; clathrate hydrate ; hydrate ; hydrogen bonding ; crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Of the various hydrates oftert-butylamine, the title compound has been identified as the second-highest, melting incongruently at −19°C. Its crystal structure (orthorhombic, space groupPca21,Z=32 formula units per unit cell,a=24.80,b=16.440,c=25.29 Å) and the exact composition have been determined from X-ray diffraction at −150°C. The hydrate is a rather complex semi-clathrate, with the amine molecules not merely encaged, but also hydrogen-bonded, in a three-dimensional water host structure, which in turn is not fully four-connected. Nevertheless, it bears a clear relationship to the basic and genuine clathrate-hydrate cubic 12 Å type.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00707689
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  • 2
    Electronic Resource
    Electronic Resource
    Polyhedral clathrate hydrates of a strong base: Phase relations and crystal structures in the system tetramethylammonium hydroxide-water (1990)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 8 (1990), S. 139-157 
    Details
    ISSN: 1573-1111
    Keywords: Tetramethylammonium hydroxide ; X-ray crystal structure ; hydrogen bonding ; clathrate hydrates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The tetramethylammonium hydroxide-water system has been studied by low-temperature differential thermal analysis and X-ray powder diffraction. The melting diagram was constructed for concentrations between 66.7 and 100 mol% H2O. It shows the existence and stability ranges of as many as eight crystalline hydrate phases:α- andβ-Me4NOH·2H2O (phase transition at −85°C, decomposition atca. 105°C), Me4NOH·4 H2O (melting point 44°C, incongruent),α andβ-Me4NOH·5 H2O (phase transition at 42°C, melting point 68°C, congruent),α- andβ-Me4NOH·7.5 H2O (phase transition at 6°C, melting point 16°C, incongruent), and Me4NOH·10 H2O (melting point −20°C, incongruent). The structures of all these phases, except the already known one ofα-Me4NOH·5 H2O, were determined from single-crystal MoKα diffractometer data. The decahydrate and the high-temperatureβ forms of the 7.5-hydrate and the pentahydrate are genuinepolyhedral clathrate hydrates, the first ones reported of a strong base. Their mostly novel three-dimensional anionic host structures, formed by the hydrogen-bonded OH− ions and H2O molecules, arefour-connected throughout, in spite of their proton deficiency which is apparently leveled by disorder. Disorder also affects the enclosed cationic Me4N+ guest species. Like the low-temperatureα form of the pentahydrate, that of the 7.5-hydrate has a clathrate-related, but not fully polyhedral structure, some of the oxygen atoms being three-connected only. The tetrahydrate presents the rare case of both a hydrogen bond of the type OH−...OH2 and a (deprotonated) water-channel structure. This is fully ordered and apart from that can be derived from the polyhedral one of theβ-pentahydrate just by removing the appropriate number of water molecules from certain positions. The structures ofα- andβ-Me4NOH·2 H2O contain identical one-dimensionalspiro chains [HO−(HOH)/42] with the hydroxide protonnot participating in the hydrogen bonding. The Me4N+ ion is ordered in theα and disordered in theβ phase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01131293
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  • 3
    Electronic Resource
    Electronic Resource
    Hydrate schwacher und starker Basen. IX. Zur Wasserstoffbrückenbindung in CsNa2(OD)3 · 6D2O: Neutronenbeugung an einem Einkristall bei 120 KProfessor Heinz Dieter Lutz zum 60. Geburtstage gewidmet (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 809-813 
    Details
    ISSN: 0044-2313
    Keywords: Cesium disodium trihydroxide hexahydrate ; deuterated material ; neutron diffraction ; hydrogen bonding ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hydrates of Weak and Strong Bases. IX. Hydrogen Bonding in CsNa2(OD)3 · 6D2O: A Single-Crystal Neutron-Diffraction Study at 120 KThe title compound is the first hydrate of a ternary alkali hydroxide reported. Its structure is related to the hexagonal perovskites and at the same time shaped by a complex system of hydrogen bonds. In a previous X-ray structure analysis at room temperature of the isotypic undeuterated material, these had been characterized only insufficiently. Therefore a complete structure determination has now been performed on a perdeuterated single crystal using low-temperature neutron-diffraction data (Pca21, Z = 4; a = 13.86, b = 6.070, c = 12.41 Å at 120 K; 1 655 observed independent reflections, R = 0.027).
    Notes: Die Titelverbindung ist das erste beschriebene Hydrat eines ternären Alkalihydroxids. Ihre Struktur ist verwandt mit der der hexagonalen Perowskite und zugleich durch ein komplexes System von Wasserstoffbrücken geprägt. Dieses war in einer vorangegangenen Röntgenstrukturanalyse bei Raumtemperatur an der isotypen nicht deuterierten Substanz nur unzureichend charakterisiert worden. Daher wurde nun eine vollständige Strukturbestimmung an einem perdeuterierten Einkristall mit Tieftemperatur-Neutronenbeugungsdaten durchgeführt (Pca21, Z = 4; a = 13,86, b = 6,070, c = 12,41 Å bei 120 K; 1 655 beobachtete unabhängige Reflexe, R = 0,027).
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19946200509
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