Dr. David Oxtoby is supported by a grant from The Theoretical and Computational Chemistry Program to use statistical mechanical techniques to study the rate of nucleation of liquids from gases and of gases from liquids, both in free space and at solid surfaces. Nucleation studies of crystallization from atomic fluids, molten salts, colloidal suspensions, molecular liquids, metals and metallic alloys will also be conducted. An understanding of the nucleation process is of fundamental importance in atmospheric science, and in chemical separations. Dr. Oxtoby has recently been successful in using density functional methodology to study the gas-liquid nucleation process. In this theory, the free energy of the system is expressed as a functional of the particle density which is assumed to be spherically symmetric. Extrema of this functional are used to characterize the transition state, both barrier height and shape, for the nucleation process. This methodology has already been successfully demonstrated for gas-liquid nucleation in simple fluids, and will now be extended to the treatment of other processes such as bubble formation and crystallization.
