Polyhedral Clathrate Hydrates. XV. The Structure of 4(CH3)3N·41H2O

Panke, D.

doi:10.1063/1.1669563

Cited by 29 publications

(8 citation statements)

References 8 publications

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“…For example, the clathrate-hydrates trimethylamine decahydrate (Panke 1968) and tetra-iso-amyl ammonium fluoride (with 38 water molecules) (Jeffrey 1984) have the same geometry as described here for the open prolamellar body. It is composed of tetrahedrally branched ultimate units, of similar geometry to those also found in carbon compounds and in aggregated water molecules in structures such as ices and clathrate inclusion compounds.…”

Section: Discussionmentioning

confidence: 96%

Membrane geometry of ?open? prolamellar bodies

Gunning

2001

Protoplasma

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The "open" type of prolamellar body in etiplasts was examined by electron microscopy to characterise its three-dimensional organisation. As in more compact forms of prolamellar body, its basic geometric unit is a tetrahedrally branched tubule. In the "open" type, these lie smoothly confluent with one another at the vertices of 5- and 6-membered rings which circumscribe the faces of three kinds of polyhedra: pentagonal dodecahedra (with 12 pentagonal faces), 14-hedra (2 opposite hexagonal faces joined by two circlets of six pentagonal faces), and 15-hedra (3 hexagonal and 12 pentagonal faces). These polyhedra join confluently in their turn, sharing faces with one another in at least one recognisable super-structure which accounts for the appearance of "open" prolamellar bodies in many ultrathin sections. In this organisation, columns of pentagonal dodecahedra are arranged at 120 degrees to one another in the x-y-plane of the lattice. They do not fill the plane but intersect so as to delimit voids in the form of hexagonally arranged 14-hedra (with hexagonal rings in the x-y-plane). Strata of this type alternate with strata made of face-sharing 15-hedra (with their hexagonal rings normal to x-y), which also delimit 14-hedra. The 14-hedra thus lie in register in the z-axis in hexagonally arranged columns, normal to the alternating strata. Other possible organisations cannot be excluded and local variations and dislocations certainly occur, but many micrographs that display elements of symmetry in "open" prolamellar bodies can be matched to thin slices through such a model. Its geometry is like that of the cages of water molecules in type IV (sensu Jeffrey = type III sensu O'Keeffe) clathrate-hydrates, point group P6/mmm, but about two orders of magnitude larger.

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Section: Discussionmentioning

confidence: 96%

Membrane geometry of ?open? prolamellar bodies

Gunning

2001

Protoplasma

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“…Some of the water molecules in the crystal units are threefold-coordinated. [6,62] Reproduced with permission from Ref. [62].…”

Section: Hydrates From Terrestrial and Oceanic Research And Drilling mentioning

confidence: 98%

Hydrates of Natural Gases and Small Molecules: Structures, Properties, and Exploitation Perspectives

Barone

Chianese

2009

ChemSusChem

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Starting from the discovery, in the mid-1930s, that petroleum pipelines in the colder regions of the Northern hemisphere contained crusts of some crystals, and were often blocked by them, a short history of the development of research on the structures, properties, and possible exploitation of the class of inclusion compounds known as gas hydrates is given. The state of the assessment of the natural reservoirs and their perspectives for exploitation are presented, together with an analysis of the hypotheses on the origins of the hydrates. Finally, the phase diagrams are shown in relation to environmental problems arising from the instability of the hydrate fields due to global warming or geological activity.

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“…Although the crystal structures of adducts of trimethylamine with iodine (Stromme, 1959), iodine chloride (Hassel & Hope, 1960), and sulphur dioxide (van der Helm, Childs & Christian, 1969), as well as the 10.25H20 clathrate (Panke, 1968), have been known for several years, molecular parameters were not accurately determined. Moreover, no solid-state structure of NMe 3 itself has been published, although a gas-phase electron diffraction study (Beagley & Hewitt, 1968), and a microwave determination (Wollrab & Laurie, 1969) have been reported.…”

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confidence: 99%