11/27 - Seminar (theoretical): John C. Tully, Yale
John C. Tully - speaker's webpage
Department of Chemistry
Host: Garnet Chan
Chemical Dynamics at Metal Surfaces: The Role of Electronic Excitations
The adiabatic (Born-Oppenheimer) approximation underlies most of our understanding of chemical reaction dynamics. It has become clear, however, that nonadiabatic electronic transitions can sometimes play an important role, particularly in photo-initiated and highly energetic reactions. It is not as widely known that for reactions at metal surfaces, even at thermal energies, nonadiabatic behavior is the rule rather than the exception. Electron-hole pair transitions, charge transfer and hot-electron-induced motion can be dominant pathways for energy flow and can drastically alter reaction pathways. Recent experiments have demonstrated that molecular vibrational energy and reaction exothermicity can produce highly excited electrons, even resulting in electron emission. This talk will present progress toward a unified picture of nonadiabatic dynamics at metal surfaces, with application to multi-quantum vibrational-to-electronic energy transfer in the scattering of nitric oxide from a gold surface.