This award from the Chemistry Research Instrumentation and Facilities (CRIF) Program and the Academic Research Infrastructure (ARI) Program will assist the Department of Chemistry at Princeton University acquire a short pulse laser system . This equipment will enhance research in a number of areas including the following: (1) structure and dynamics of proteins and porphyrin excited states (2) time resolved chemical dynamics and spectroscopy on/in liquid helium clusters (3) time dependent anti-Stokes Raman study of intramolecular vibrational energy redistribution (4) coherent control of chemical dynamics (5) electron transfer studies in biological and solid state systems, and (6) two electron charge transfer processes. A tunable laser can provide important information about chemical reactivity. Its use may enable breakthroughs in our understanding of the properties of reactivity and nonreactivity of molecules.