Presentation description

Liquid-liquid interfaces are an important area of study due to their prevalence in biological systems, industrial purification processes, and liquid-liquid extraction in organic chemistry. Understanding the rate of transport of small molecules across these interfaces can help us to optimize these processes and better control reaction rates and yields. Different isomers of hexane have been associated with different rates of transport across the hexane-water interface through electrochemical methods that measure the oxidation of ferrocene that is simultaneous with the transport of the ferrocene across the interface. To get a closer look at this system, we use Molecular Dynamics (MD) to investigate the interfacial organization and solvent transport properties for a series of hexane isomers. Organization is studied through descriptors of solvent orientation, while transport is studied by the residence times of solvent molecules at the oil/water surface. We find that the hexane isomers with less branching have more exchange from the bulk to the interface, and experimentally higher rates of ferrocene oxidation. By modeling the molecular behavior of oil/water interfaces, we can complement experimental observations of transport behavior that may be altered by changes to solvent transport to and from the interface.