In this project in the Experimental Physical Chemistry Program, David Nesbitt of the University of Colorado will investigate the potential energy surfaces of van der Waals molecules using laser based spectroscopic methods. These studies will concentrate on hydrogen bonded species and multiple rare-gas cluster systems including HF, HCL, and water. Additional work will focus on the production and infrared characterization of radical and radical complexes of important atmospheric components such as the peroxyl radical, and the spectroscopy and dynamics of prototypical heavy-light-heavy reactive systems such as Cl-HCl and F-HF. High resolution near infrared light will be used to state-select a cluster which will be subsequently photolyzed in studies involving reactive and inelastic scattering. These systems include DCl-HCl and XH-NNO (ONN), and provide control over cluster size, quantum state, and reactant approach geometry. The determination of potential energy surfaces provides the information needed to understand and control the course of a chemical reaction. Professor Nesbitt's studies will provide quantum state specificity and a specific reactant approach geometry for an important class of chemical reactions known as heavy-light-heavy reactions. The information obtained from this work will be an important step towards using lasers to control of the outcome of chemical reactions.