期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1974
卷号：71
期号：8
页码：2925-2927
DOI：10.1073/pnas.71.8.2925
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The unitary free energy of transfer of a hydrocarbon molecule from a hydrocarbon solvent to an aqueous medium is a measure of the hydrophobic interaction in the aqueous medium. We have reexamined available data on this phenomenon and have confirmed that the free energy for saturated hydrocarbons is proportional to the surface area of the cavity created by the solute in the aqueous solution, with the same proportionality constant for linear, branched, and cyclic hydrocarbon molecules. The numerical value of the proportionality constant is uncertain because absolute and self-consistent area measurements are not available. We estimate that it falls between 20 and 25 cal/mole per A2 at 25{degrees} (for areas measured at the distance of closest approach of water molecules), which is significantly less than the figure of 33 cal/mole per A2 that has been assigned to the same parameter by Hermann [J. Phys. Chem. 76, 2754-2759 (1972)]. A small discrepancy exists when similar data for homologous series of alkyl derivatives are compared with results based on hydrocarbons themselves, and possible reasons for it are discussed.
关键词：hydrophobic effect ; hydrocarbons ; water structure
