Solvophobic solvation at large and intermediate length scales: Size, shape, and solvent effects

We report the results of molecular-dynamics simulations of solvophobic nanoparticles in n-decane solvent. We observe that solvent ordering in the interparticle gap and solvation forces depend on the particle size and shape. Analogous to hydrophobic hydration, we observe dewetting of the interparticle region when the nanoparticle separation becomes smaller than a critical value of _c. We observe that _c exhibits a nonmonotonic dependence on nanoparticle size, in contrast to what is expected from studies of water. While studies of hydrophobic hydration indicate that two solute length scales govern hydrophobic interactions, our studies indicate that a third length scale can be important in the more general phenomenon of solvophobic solvation.

©2006 The American Physical Society