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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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AACP Seminar Series - Prof. Marsha Lester, University of Pennsylvania
Collisional Quenching of OH Radicals: Dynamical Outcomes
The nascent OH X2Î product state distributions arising from collisional quenching of electronically excited OH A2Σ+ by several molecular partners have been determined using a pump-probe technique. For H2 and N2 collision partners, the majority of OH X2Î products are observed in their lowest vibrational level, vâ³=0, with significantly less population in vâ³=1. The OH (vâ³=0) products are generated with a substantial degree of rotational excitation, peaking around Nâ³=15 with H2 as the collision partner and Nâ³=18 with N2. Complementary measurements of the branching fraction into OH 2Î product states demonstrate that reaction is the dominant decay pathway for quenching of OH A2Σ+ by H2, while nonreactive quenching is the dominant pathway for N2. These observations are discussed in the context of theoretical calculations that examine the topography of the conical intersections which couple the electronically excited and ground state potential energy surfaces. The experimental observables are interpreted as dynamical signatures of nonadiabatic passage through the conical intersection regions responsible for quenching in both systems.
For more information contact Prof. Christine Payne (404-385-3125).
