Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-17T18:55:29.289Z Has data issue: false hasContentIssue false
  • English
  • Français

Entropy of Hydrophobic Hydration: A New Statistical Mechanical Formulation

Published online by Cambridge University Press:  26 February 2011

Themis Lazaridis  and
Michael E. Paulaitis
Themis Lazaridis
Affiliation:
University of Delaware, Department of Chemical Engineering, Newark, Delaware 19716
Michael E. Paulaitis
Affiliation:
University of Delaware, Department of Chemical Engineering, Newark, Delaware 19716
Get access

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.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 278: Symposium W – Computational Methods in Materials Science , 1992 , 319
Copyright
Copyright © Materials Research Society 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Wallace, D. C. J. Chem. Phys. L7, 2282 (1987); Phys. Rev. A 38, 469 (1988); Phys. Rev. A 39, 4843 (1989); Proc. R. Soc. Lond. A 433, 615 (1991).Google Scholar
2. Green, H. S., The Molecular Theory of Fluids (North-Holland, Amsterdam, 1952).Google Scholar
3. and, C. G. Gray Gubbins, K. E., Theory of Molecular Fluids, vol. 1 (Clarendon Press, Oxford, 1984), chapter 3.Google Scholar
4. Lazaridis, T., and Paulaitis, M. E., J. Phys. Chem., 1992 (in press).Google Scholar
5. Kirkwood, J. G., J. Chem. Phys. 10, 394 (1942).CrossRefGoogle Scholar
6. Baranyai, A. and Evans, D. J., Phys. Rev. A 40,3817 (1989).Google Scholar
7. Baranyai, A. and Evans, D. J., Phys. Rev. A 42,849 (1990).CrossRefGoogle Scholar
8. Jorgensen, W. L.. BOSS version 2.8, (Yale University, New Haven, Connecticut, 1989).Google Scholar
9. Jorgensen, W. L., Chandrasekhar, J., Madura, J. D., Impey, R. W., and Klein, M. L., J. Chem. Phys. 79, 926 (1983).Google Scholar
10. Owicki, J. C. and Scheraga, H. A., Chem. Phys. Lett. 47, 600 (1977).Google Scholar
11. Ben-Naim, A. and Marcus, Y., J. Chem. Phys. BI, 2016 (1984).Google Scholar
12. Naghibi, H., Dec, S. F. and Gill, S. J., J. Phys. Chem. 90, 4621 (1986).CrossRefGoogle Scholar
13. Rettich, T. R., Handa, Y. P., R. Battino and Wilhelm, E., J. Phys. Chem. 85, 3230 (1981).Google Scholar
14. Pollack, G. L., Science 251, 1323 (1991).Google Scholar