Ultrafast Spectroscopy and Other Applications of Lasers in Chemistry

University Of Pennsylvania, Philadelphia PA

Investigators

Abstract

Professor Robin Hochstrasser of the University of Pennsylvania is funded by the Experimental Physical Chemistry program to perform experiments on liquid phase chemical dynamics. This proposal represents the systematic development of two-dimensional time-resolved infrared spectroscopies, which Professor Hochstrasser has pioneered. These methods, which have analogs in the microwave region using NMR, can yield highly detailed information about molecular vibrational dynamics and coupling and the structures of the liquid samples themselves. Two dimensional IR studies on polypeptides are aimed at improving our understanding of the structure and dynamics of proteins. Other multidimensional laser experiments are aimed at gaining new insights into the structure and dynamics of liquids, including neat water, and polymers. The work on two-dimensional infrared spectroscopy is extremely timely in addressing the need for new methods to provide breakthroughs in determining protein, polymer and liquid structures. Instead of the traditional way of thinking about molecules as discrete particles in solution, this work introduces a new paradigm -- molecules are considered as extended networks of coupled vibrators. Accurate pictures of liquid structures provide some of the key information necessary for addressing biomolecular and environmental problems.