Entropy of hydrophobic hydration: a new statistical mechanical formulation

Themis Lazaridis, Michael Paulaitis

Research output: Contribution to journalArticle

Abstract

A statistical mechanical formulation is presented for the entropy of solution of simple molecules in water. The formulation is based on the Green-Wallace expansion for the entropy in terms of multiparticle correlation functions, which is derived here for rigid polyatomic fluids and for mixtures. With a factorization assumption for the solute-water correlation function we have been able to separate the translational and orientational contributions to the entropy of solution. This approach is applied to an infinitely dilute solution of methane in water. The required correlation functions are obtained by Monte Carlo simulation. The orientational contribution, which is due directly to the orientational asymmetry of water-water interactions, is found to be comparable to the translational contribution. We find that the large entropies and heat capacities of hydrophobic hydration can be accounted for by solute-water correlations alone and that large perturbations in water structure are not required to explain hydrophobic behavior.

Original languageEnglish (US)
Pages (from-to)43-49
Number of pages7
JournalFluid Phase Equilibria
Volume83
Issue numberC
DOIs
StatePublished - 1993
Externally publishedYes

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Hydration
hydration
Entropy
entropy
formulations
Water
water
solutes
Methane
Factorization
factorization
Specific heat
methane
asymmetry
specific heat
perturbation
Molecules
expansion
Fluids
fluids

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Physical and Theoretical Chemistry

Cite this

Entropy of hydrophobic hydration : a new statistical mechanical formulation. / Lazaridis, Themis; Paulaitis, Michael.

In: Fluid Phase Equilibria, Vol. 83, No. C, 1993, p. 43-49.

Research output: Contribution to journalArticle

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