Professor Reiss is supported by a grant from the Experimental Physical Chemistry Program for the experimental and theoretical investigation of nucleation, the process by which an aggregate of molecules too small to be observed becomes the nucleus upon which other molecules condense in the vapor phase, which leads eventually to the formation of a liquid droplet. The experiments are carried out in a cloud chamber, and the goal is the understanding at the molecular level of the physical cluster itself and the physical process by which it is formed. The theoretical and experimental studies in this research involve a molecular theory of vapor phase nucleation, capable of quantitative prediction of critical supersaturation for homogeneous nucleation in single and multicomponent systems under conditions of practical interest. Studies of vapor phase nucleation of vinyl polymers will be based on the same theory. The theory involves the identification of the physical cluster consistent with the physical process of nucleation and the analysis of that cluster with Monte Carlo simulation.
