Static and Dynamical Models of Network Liquids

Oregon State University, Corvallis OR

Investigators

Abstract

Professor Glenn T. Evans is supported by the Theoretical and Computational Chemistry Program to develop a theory for self-assembling liquids that is determined from static and dynamical models of network liquids. The primary focus is on the use of equilibrium and nonequilibrium statistical mechanical techniques to study a basic model of water. The goal of this research is to determine whether such a model can emulate the essential aspects of hydrogen-bonded networks that are associated with real water. Reproducing features of hydrogen bonding within computationally feasible approaches continues to be a challenging goal. Methods used for the equilibrium studies rely upon Wertheim's integral equation theory for associating fluids coupled with classical density functional theory and Monte-Carlo simulations. Dynamical studies employ kinetic theory, time-dependent Ginzburg-Landau theory and computer simulations. Techniques are also amenable to the study of dendrimer and micelle formation. The unique properties of water are largely due to a weak interaction between hydrogen atoms on one molecule and the oxygen atoms on another molecule. This deceptively simple interaction continues to present a challenge to researchers interested in computer simulation of water and more complicated network liquids. Understanding how to model these interactions is important since the same interactions are responsible for the self-assembly of micelles, dendrimers and cell membranes. In this work, advanced theories are used in conjunction with simple models of water interactions to determine if such models are capable of reproducing the salient features of water. The research program is coupled to a strong undergraduate training initiative that gives undergraduates experience in development and application of their own software tools for understanding the properties of water.