Abstract
A combined quantum mechanical and molecular mechanical Monte Carlo simulation method was used to determine the free energy of binding between tetramethylammonium ion (TMA+) and benzene in water. The computed free energy as a function of distance (the potential of mean force) has two minima that represent contact and solvent-separated complexes. These species are separated by a broad barrier of about 3 kJ/mol. The results are in good accord with experimental data and suggest that TMA+ binds to benzene more favorably than to chloride ion, with an association constant of about 0.8 M-1.
Original language | English (US) |
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Pages (from-to) | 43-47 |
Number of pages | 5 |
Journal | Biophysical journal |
Volume | 65 |
Issue number | 1 |
DOIs | |
State | Published - 1993 |
Bibliographical note
Funding Information:The National Institutes of Health (to J. Gao) and the National Science Foundation (to A. Auerbach) provided support for this research. The calculations were done on IBM RS/6000 computers at the State University of New York at Buffalo.