TY - JOUR
T1 - Monte Carlo computer simulation study of the hydrophobic effect
T2 - Potential of mean force for [(CH4)2]aq at 25 and 50 °C
AU - Ravishanker, Ganesan
AU - Mezei, Mihaly
AU - Beveridge, David L.
N1 - Funding Information:
11 and 14 and the interaction of this molecule with the other waters is clearly evident. FIG 14.-Typical structure corresponding to most probable configuration in window 4. This research was supported by the General Medical Sciences Division of the U.S. National Institute of Health (grant GM24149) and a CUNY Faculty Research Award. W. Kauzrnann Adu. Protein Chem. 1959 14 1. C. Tanford The Hydrophobic Effect (Wiley New York 1973). D. N. Glew J. Phys. Chem. 1962 66 605. 'H. G. Hertz and C. Radle Ber. Bunsenges. Phys. Chem. 1973 77,521. J. C. Owicki and H. A. Scheraga J. Am. Chem. Soc. 1977,99 7413. S. Swaminathan S. W. Harrison and D. L. Beveridge J. Am. Chem. Soc. 1978 100 5705. (a) M. Mezei and D. L. Beveridge J. Chem. Phys. 1981 74 622; (6) G.
PY - 1982
Y1 - 1982
N2 - A series of liquid-state computer simulations has been performed on the system [(CH4)2]aq at 25 °C as a function of the separation R between the dissolved CH4 molecules. The potential functions for H2O-H2O, CH4-H2O and CH4-CH4 are based on quantum-mechanical calculations of the corresponding intermolecular interactions. The simulation was carried out by the Monte Carlo method augmented with convergence acceleration techniques involving force-bias and the method of preferential sampling. The potential of mean force wss(R) for the interaction of the apolar species in water was determined using umbrella sampling procedures on four windows on the intersolute coordinate. Convergence acceleration was found to be necessary for obtaining satisfactory results. Contact and solvent-separated contributions to the statistical state of the system are discussed in terms of the radial distribution functions, quasi-component distribution functions for coordination number, binding energy and pair interaction energies. Stereographic views of significant structures are presented, and contributions of clathrate structures in the solvent are discussed. The results are discussed in the context of the experimentally observed concentration dependence of hydrophobic effects and related theoretical work on wss(R) by Marcelja, Mitchell, Ninham and Scully, Pratt and Chandler, and Pangali, Rao and Berne. Prospects for quantitative study of the temperature dependence of the hydrophobic interaction and other quantitative extensions of the work are discussed.
AB - A series of liquid-state computer simulations has been performed on the system [(CH4)2]aq at 25 °C as a function of the separation R between the dissolved CH4 molecules. The potential functions for H2O-H2O, CH4-H2O and CH4-CH4 are based on quantum-mechanical calculations of the corresponding intermolecular interactions. The simulation was carried out by the Monte Carlo method augmented with convergence acceleration techniques involving force-bias and the method of preferential sampling. The potential of mean force wss(R) for the interaction of the apolar species in water was determined using umbrella sampling procedures on four windows on the intersolute coordinate. Convergence acceleration was found to be necessary for obtaining satisfactory results. Contact and solvent-separated contributions to the statistical state of the system are discussed in terms of the radial distribution functions, quasi-component distribution functions for coordination number, binding energy and pair interaction energies. Stereographic views of significant structures are presented, and contributions of clathrate structures in the solvent are discussed. The results are discussed in the context of the experimentally observed concentration dependence of hydrophobic effects and related theoretical work on wss(R) by Marcelja, Mitchell, Ninham and Scully, Pratt and Chandler, and Pangali, Rao and Berne. Prospects for quantitative study of the temperature dependence of the hydrophobic interaction and other quantitative extensions of the work are discussed.
UR - http://www.scopus.com/inward/record.url?scp=2742595274&partnerID=8YFLogxK
U2 - 10.1039/FS9821700079
DO - 10.1039/FS9821700079
M3 - Article
AN - SCOPUS:2742595274
SN - 0301-5696
VL - 17
SP - 79
EP - 91
JO - Faraday Symposia of the Chemical Society
JF - Faraday Symposia of the Chemical Society
ER -