January 20, 2015 - 11:00am
Wright Rieman Auditorium
"The Role of Solvent Fluctuations in the Kinetics of Hydrophobic Assembly and Ligand Binding"
Spring 2015 Colloquium Series
|Speaker: Joseph Morrone
Stony Brook University
|Abstract: Water plays an important role in self-assembly and ligand binding. In order to elucidate the influence of solvent-mediated effects on the kinetics of association, we study the assembly of nanoscale hydrophobes and a ligand into a model cavity. From molecular dynamics simulations with explicit solvent, we determine the free energy surfaces and hydrodynamic interactions when the bodies are strongly and weakly hydrophobic. Molecular scale effects such as drying and solvent layering are found to dominate at small separations, thus giving rise to deviations from the predictions of continuum hydrodynamic theory. Regions of high friction are engendered by large and slow solvent fluctuations. In light of these findings, we also evaluate the assumption of fast solvent relaxation times that is inherent in the Brownian description of diffusion-controlled reactions. To this end a "non-Markovian Brownian theory" is introduced which accounts for slow solvent motions utilizing a coarse-grained dynamical scheme.|
|~ Coffee/tea will be served prior to lecture ~|