Grant: Discovery Grants Program - Individual

This proposal concerns the equilibrium and dynamical theory of liquids and solutions. We consider both bulk homogeneous phases and interfacial systems. The research program emphasizes the development of theoretical methods and their application to systems of physical interest. To achieve this end, we employ a combination of analytical statistical mechanical theories and computer simulation techniques. Principal areas of current research are as follows: (1) Nematic Fluids with Wall and Field Interactions: Ordering of Nematic Colloids. Nematic liquid crystals near solid surfaces are a topic of intense research both for their intrinsic interest, and because of their key role in display devices. Such interactions are also important in a new type of materials, nematic colloids. Our objective is to gain a microscopic understanding of these systems. (2) Protein Denaturation and Osmolyte Intervention. Small organic molecules called osmolytes play a crucial role in protecting biological organisms under osmotic (water) stress. Our focus is on understanding how the osmolyte, trimethylamine-N-oxide, prevents protein denaturation in stressful conditions. (3) Water Adsorption and Ice Nucleation on Clay. This is relevant to atmospheric science, particularly to cloud formation. The aim is to better understand the water adsorption and ice nucleation properties of particular treated and untreated clay particles. (4) Structure, Phase Transitions, and Interactions in Confined Fluids. It is now recognized that phase-change-related phenomena can induce long-range forces between immersed objects ranging in size from large molecules, to colloidal particles, to surfaces. These forces can influence physically important processes such as coagulation of colloidal suspensions, and possibly the configuration of polymers in solution. We are interested in new but related effects that emerge for chemically patterned plates or particles immersed in binary mixtures, and for water and ions in patterned nanopores. (5) Coulombic Fluids. Our focus is on understanding the important molecular factors that contribute to the structure and dynamics of room temperature ionic liquid.