Wydział Chemii

Nadya Kobko

M. Marianski

A. Asensio

Robert Wieczorek

J. J. Dannenberg

2012

Computational and Theoretical Chemistry

990

214-221

10.1016/j.comptc.2011.11.022

Naukowa

Angielski

Artykuł

The physical explanation for the hydrophobic effect has been the subject of disagreement. Physical organic chemists tend to use an explanation related to pressure, while many biochemists prefer an explanation that involves decreased entropy of the aqueous solvent. We present DFT calculations at the B3LYP/6-31G(d,p) and X3LYP/6-31G(d,p) levels on the solvation of three noble gases (Ne, Ar, and Kr) in clusters of 50 waters. Vibrational analyses show no substantial decreases in the vibrational entropies of the waters in any of the three clusters. The observed positive free energies of transfer from the gas phase or from nonpolar solvents to water appear to be due to the work needed to make a suitable hole in the aqueous solvent. We distinguish between hydrophobic solvations (explicitly studied here) and the hydrophobic effect that occurs when a solute (or transition state) can decrease its volume through conformational change (which is not possible for the noble gases).

hydrophobic, DFT, Water, solvation

https://doi.org/10.1016/j.comptc.2011.11.022

http://www.elsevier.com