In this National Science Foundation New Young Investigator (NYI) project of the Physical Chemistry Program in the Chemistry Division Prof. Yongqin Chen of the University of California at Berkeley will investigate the transition state chemistry in photodissociation and chemical reactions in real-time. This will be accomplished with a new technique of his design, transient stimulated emission pumping (TSEP), which enables the probing of chemical processes on a femtosecond time scale. These investigations will be performed on gaseous systems as well as on supercritical fluids. %%% Chemical reaction dynamics is at the forefront of present research in chemistry. The details of how a chemical reaction proceeds can only be studied on time scales which are of the order of the period of one molecular vibration or less. To carry out such investigations requires experimental techniques with ultra fast time resolution, on time scales ranging from pico- to femtoseconds. The new TSEP technique possesses considerable advantages over other, currently used techniques by, for example, generating an entire stimulated emission spectrum simultaneously rather than by point-by-point scanning.
