Induction cluster polarization, structure

To find out for certain if a special structure is induced in water by non-polar groups, Grunwald and Ralph (1967) measured the rate-constant for breaking the hydrogen bond that unites a tertiary amine to water, as in R N-HOH. Here, R was a hydrocarbon group whose size was systematically increased. The results showed no evidence of the induction of ice-like structure by the hydro-phobic groups. Another difficulty preventing acceptance of the hydrate hypotheses is that the cavity within ice clusters can accommodate only spherical molecules and hence, when a hydrocarbon series is ascended, the ability to form hydrates is lost whereas anaesthetic activity increases. Diethyl ether, most typical of the anaesthetics, is a rather flat, butterfly-shaped molecule that forms no crystalline hydrate. 

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