Iceberg hypothesis

Several key issues have been addressed in these published simulations, but the one receiving most attention involves the structural origin of the entropy of hydrophobic hydration. The classic perspective on this issue, originally put forth by Frank and Evans as the iceberg hypothesis, involves an ordering of water molecules in the hydration shell of the nonpolar solute. 

Stabilization of the hydrogen bond network. This is in apparent conflict with solvent ordering predicted by the iceberg hypothesis. 

Models of hydrophobic hydration including the iceberg hypothesis and its more modern variants have led to several qualitative predictions for pairwise hydrophobic interactions. The first and simplest prediction based on free-energy arguments is that nonpolar solutes should tend to associate... 

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