This award supports Professor Sheng Hsien Lin of Arizona State University for several short term visits to collaborate with Prof. E. W. Schlag of the Technical University of Munich. They are studying the mechanisms of laser-stimulated desorption or vaporization of adsorbed molecules from solid surfaces, using both infrared and ultraviolet-visible lasers. They plan to continue their investigation of spectral shifts and electronic relaxation of van der Waals complexes. In addition, they will study the spectroscopic properties and dynamical processes of benzene and other dimers and the photoisomerization of an aromatic molecule embedded in a cluster as a function of cluster size. They will also carry out a theoretical study of photoionization threshold spectroscopy on van der Waals clusters to show that this leads to more accurate determination of ionization potential and provides information on the structure and vibrational frequencies of the cluster. Professor Lin is carrying out state of the art theoretical research on problems of great current interest in chemistry - studies of laser-stimulated vaporization of molecules from surfaces and of the spectral properties of van der Waals complexes. Such work requires input from experiments. Collaboration with Dr. Schlag and his outstanding group of experimentalists provides this very necessary interaction. Their prior collaboration has produced a number of significant contributions. Current plans for further collaboration promise valuable new insights into the processes that take place in a molecule after it has absorbed energy from light.
