Model for the hydration of non-polar compounds and polymers

Pierpaolo Bruscolini; Lapo Casetti

doi:10.1103/physreve.64.051805

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arXiv · cond-mat/0201254

Model for the hydration of non-polar compounds and polymers

Pierpaolo Bruscolini·Lapo Casetti

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Abstract

We introduce an exactly solvable statistical-mechanical model of the hydration of non-polar compounds, based on grouping water molecules in clusters where hydrogen bonds and isotropic interactions occur; interactions between clusters are neglected. Analytical results show that an effective strengthening of hydrogen bonds in the presence of the solute, together with a geometric reorganization of water molecules, are enough to yield hydrophobic behavior. We extend our model to describe a non-polar homopolymer in aqueous solution, obtaining a clear evidence of both ``cold'' and ``warm'' swelling transitions. This suggests that our model could be relevant to describe some features of protein folding.

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Pierpaolo Bruscolini, Lapo Casetti. 2002-01-15. Model for the hydration of non-polar compounds and polymers. https://doi.org/10.1103/physreve.64.051805

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