In the Beginning Hoffman Inclusion Compounds and Werner Clathrates

4 In the Beginning Hoffman Inclusion Compounds and Werner Clathrates 

Soldatov, D. V., Enright, G. D., Ripmeester, J. A., Polymorphism and pseudopolymorphism of the [Ni(4-methylpyridine)4(NCS)2] Werner complex, the compound that led to the concept of organic zeolites , Cryst. Growth Des. 2004, 4, 1185-1194. 

4 (first reported in 1957) and some analogues is that slow removal of guests can result in the formation of a microporous, guest-free apohost j8o-phase. 

The important part is step 2, the guest release. For the clathrate /-form this process occurs over a narrow temperature range bracketed by two plateaus corresponding to the initial (y) and final (a) phases. This behaviour is typical of clathrates. In contrast, for the 8-phase, guest release is continuous over the entire temperature range until the host complex decomposes. This kind of desolvation behaviour in which guests slowly exit a channel that remains intact is characteristic of zeolites. 

1 Thennogravimetric Analysis and Differential Scanning Calorimetry in the Study of Inclusion Compounds 

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