Dr. Mark A. Smith is supported by a grant from the Experimental Physical Chemistry Program to study ion-molecule reactions at temperatures approaching absolute zero. These measurements provide valuable insight into the mechanism of molecular synthesis in interstellar clouds where these conditions are approached. Smith is pursuing a two pronged approach aimed at advancing the methodology for the direct study of molecular collision dynamics in the ultralow energy regime. One portion of this program is directed at obtaining a detailed characterization of the rotational and parallel translational degrees of freedom for small molecules as they exit the free jet. This data will provide critical input for the fundamental advancement of supersonic flow theory for gaseous mixtures. In the second portion of the program of study the results from the flow characterization studies are used to better interpret kinetic observations of termolecular ion association reactions in the 4 to 30 K regime.
