Professor John Fourkas of Boston College is funded by the Experimental Physical Chemistry program to conduct experimental and theoretical studies on the dynamics and structure of bulk and confined liquids. While decades of ultrafast laser studies have revealed much about bulk liquid structure and solvation phenomena, the more complex problem of liquids in nanoporous structures is a new horizon in this field. Pools of liquids consisting of 100 molecules or less are typical. This proposal seeks to make measurements on liquids in sol-gel glasses, with the specific goals of determining how molecular shape influences liquid dynamics, how extreme confinement affects the behavior of liquids and how confinement affects phase-transition temperatures. The PI then proposes to conduct theoretical studies on liquids, adding the effects of anharmonicity of the intermolecular potential of a liquid into the computation of correlation functions using instantaneous normal mode theory. A successful outcome of this proposal would be new models of confined liquids that could predict phenomena relevant to geochemistry and biochemistry.
Solvation has extremely important industrial applications, and a more complete theoretical understanding of this phenomenon could have an important impact. Practical examples of liquids in confined spaces include hydrocarbons in porous rocks, and water structured by biological molecules. There are also environmental implications of this work, in addressing the issue of flow of water and dissolved species in porous rock.