(127a) Hydrophobic Effects On a Molecular Scale

Hydrophobic interactions, ubiquitous in nature, play an important role in various phenomena such as
protein folding, lotus-effect, micelle formation, and vesicle formation. Numerous experiments have
been done to understand the physics behind this effect, but ambiguities still exist particularly at short
distances (< 10Å) [1]. In addition, experiments have not answered questions concerning the effect of
size and shape on the potential of mean force between hydrophobic solutes. Here we analyze a system
of hydrophobic solute in water using Wertheim’s first order thermodynamic perturbation theory within
a Density Functional formalism[2]. Specifically, the potential of mean force between the hydrophobic
solutes and the structuring of water around the solutes have been studied. The effect of various
parameters such as solute size, solute concentration, temperature, and solute-solute and solute-water
attraction on the potential of mean force has also been analyzed.

References
1. Meyer, E.E., K.J. Rosenberg, and J. Israelachvili, Proceedings of the National Academy of
Sciences, 2006. 103(43): p. 15739-15746.
2. Segura, C.J., W.G. Chapman, and K.S. Shukla, Mol. Phys., 1997. 90: p. 759.