Clathrate structure description

There may thus arise a structural combination of two substances which remain associated not through strong attraction between them but because strong mutual binding of the molecules of one sort only makes possible the enclosure of the other. It is suggested that the general character of this type of combination should be indicated by the description clathrate compound— clathratus , enclosed or protected by cross bars of a grating. 

Classical Descriptions of Inclusion Compounds, p. 253 Classification and Nomenclature of Supramolecular Compounds, p. 261 Clathrate Hydrates, p. 274 Concepts in Crystal Engineering, p. 519 Crystal Structure Prediction, p. 371 Cyclodextrins, p. 398... 

Further to this basic description, it is then suggested that the synthesis displays characteristics of a quasi-epitaxial growth scenario . First, the dual ownership of several common diffraction peaks indicates a growth process where there is structural continuity between elements of both phases at the NaSi/NagSi46 interface. We noted that in the early stages of clathrate formation the unit cell volume of the clathrate is anomalously low (by 0.14 %), but with time it rises to the constant value expected for the bulk clathrate. This behavior is also consistent with a quasi-epitaxial growth scenario. New clathrate material forms at the Naj. Si/... 

The clathrate nature of hydrates was not confirmed until the early 1950s, and by 1960 a theoretical description of clathrates became available. This point in time can be taken as the start of clathrate science as based on structural and molecular principles, thus opening this field to a... 

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