Monte Carlo simulation of n‐butane in water. Conformational evidence for the hydrophobic effect

Monte Carlo statistical mechanics simulations have been carried out for a dilute solution of n‐butane in water at 25 °C and 1 atm. The intermolecular interactions were described by Coulomb and Lennard‐Jones terms in the TIPS format including the TIPS2 parameters for water. The internal rotation about the central CC bond in n‐butane was included using a rotational potential based on molecular mechanics (MM2) calculations. The precision of the simulation results was enhanced by preferential sampling and by umbrella sampling for the internal rotation over chopped barriers. Conformational results are also reported from a long Monte Carlo run for pure liquid n‐butane using umbrella sampling. Although no condensed phase effect is found on the conformational equilibrium in pure liquid n‐butane, there is a pronounced increase in the gauche population of n‐butane upon transfer from the gas phase to aqueous solution. The latter finding is in near quantitative accord with the shift predicted by Pratt and Chandler fr...

[1]  W. L. Jorgensen.  Quantum and statistical mechanical studies of liquids. 10. Transferable intermolecular potential functions for water, alcohols, and ethers. Application to liquid water , 2002 .

[2]  W. L. Jorgensen,et al.  Monte Carlo simulations of liquid tetrahydrofuran including pseudorotation , 1982 .

[3]  W. L. Jorgensen.  Revised TIPS for simulations of liquid water and aqueous solutions , 1982 .

[4]  W. L. Jorgensen,et al.  Quantum and statistical mechanical studies of liquids. 21. The nature of dilute solutions of sodium and methoxide ions in methanol , 1982 .

[5]  W. L. Jorgensen,et al.  Quantum and statistical mechanical studies of liquids. Part 22. Pressure dependence of mixing enantiomeric liquids: 1,2-dichloropropane , 1982 .

[6]  M. Abraham.  Free energies, enthalpies, and entropies of solution of gaseous nonpolar nonelectrolytes in water and nonaqueous solvents. The hydrophobic effect , 1982 .

[7]  J. Rabolt,et al.  An investigation of the conformational equilibrium of n‐butane in a solvent using Raman spectroscopy , 1982 .

[8]  M. Winnik.  Cyclization and the conformation of hydrocarbon chains , 1981 .

[9]  W. L. Jorgensen,et al.  Sampling methods for Monte Carlo simulations of n‐butane in dilute solution , 1981 .

[10]  W. L. Jorgensen.  Pressure dependence of the structure and properties of liquid n-butane , 1981 .

[11]  W. L. Jorgensen,et al.  Structures and properties of organic liquids: n-butane and 1,2-dichloroethane and their conformation equilibriums , 1981 .

[12]  K. Nakanishi,et al.  A Monte Carlo study on the size dependence in hydrophobic hydration , 1981 .

[13]  W. Murphy,et al.  Low-frequency Raman spectrum and asymmetric potential function for internal rotation of gaseous n-butane , 1980 .

[14]  D. Chandler,et al.  Hydrophobic solvation of nonspherical solutes , 1980 .

[15]  R. G. Snyder,et al.  Raman spectra of liquid n‐alkanes. III. Energy difference between trans and gauchen‐butane , 1980 .

[16]  H. Berendsen,et al.  INFLUENCE OF HYDROPHOBIC SOLUTES ON THE DYNAMIC BEHAVIOR OF WATER , 1980 .

[17]  L. Colombo,et al.  Enthalpy difference of rotational isomers in liquid butane and pentane from infrared spectra , 1980 .

[18]  D. H. Wertz.  Relationship between the gas-phase entropies of molecules and their entropies of solvation in water and 1-octanol , 1980 .

[19]  S. Profeta,et al.  The torsional potential function for n‐butane , 1980 .

[20]  David Chandler,et al.  Comment on the role of constraints on the conformational structure of n‐butane in liquid solvents , 1979 .

[21]  Bruce J. Berne,et al.  A molecular dynamics and Monte Carlo study of solvent effects on the conformational equilibrium of n‐butane in CCl4a),b) , 1979 .

[22]  M. Fixman,et al.  Simulation of polymer dynamics. I. General theory , 1978 .

[23]  J. Owicki.  Optimization of Sampling Algorithms in Monte Carlo Calculations on Fluids , 1978 .

[24]  D. Chandler,et al.  Statistical mechanics of small chain molecules in liquids. I. Effects of liquid packing on conformational structures , 1978 .

[25]  Norman L. Allinger,et al.  Conformational analysis. 130. MM2. A hydrocarbon force field utilizing V1 and V2 torsional terms , 1977 .

[26]  H. Scheraga,et al.  MONTE CARLO CALCULATIONS IN THE ISOTHERMAL-ISOBARIC ENSEMBLE. 1. LIQUID WATER , 1977 .

[27]  D. Chandler,et al.  Theory of the hydrophobic effect , 1977 .

[28]  R. Pierotti,et al.  A scaled particle theory of aqueous and nonaqueous solutions , 1976 .

[29]  B. Zwolinski,et al.  Ideals gas thermodynamic properties and isomerization of n‐butane and isobutane , 1975 .

[30]  K. Tanabe,et al.  Vibrational frequencies, infrared absorption intensities and energy differences between rotational isomers of propyl halides , 1975 .

[31]  John S. Muenter,et al.  Microwave spectrum and structure of hydrogen bonded water dimer , 1974 .

[32]  Frank H. Stillinger,et al.  Structure in aqueous solutions of nonpolar solutes from the standpoint of scaled-particle theory , 1973 .

[33]  H. A. Levy,et al.  Liquid Water: Molecular Correlation Functions from X‐Ray Diffraction , 1971 .

[34]  J. E. Piercy,et al.  Ultrasonic Relaxation Due to trans—gauche Rotational Isomerism in the Liquid Normal Paraffins , 1967 .

[35]  W. L. Masterton.  Partial Molal Volumes of Hydrocarbons in Water Solution , 1954 .

[36]  Charles Tanford,et al.  The hydrophobic effect , 1980 .

[37]  Alfons Geiger,et al.  Molecular dynamics study of the hydration of Lennard‐Jones solutes , 1979 .

[38]  Jean-Paul Ryckaert,et al.  Molecular dynamics of liquid alkanes , 1978 .

[39]  A. Ben-Naim,et al.  Hydrophobic interaction in light and heavy water , 1973 .