Collision induced intramolecular vibrational energy redistribution: A classical molecular dynamics study

PHYS 428

Philip J Stimac,, Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48108 and John R Barker,, Department of Atmospheric, Oceanic, and Space Sciences & Chemistry Department, University of Michigan, 2455 Hayward, 1520 Space Research Building, Ann Arbor, MI 48109-2143.
The rates of intramolecular energy redistribution (IVR) are of significant importance in determining whether a chemical process will be well modeled by the statistical rate theory developed by Rice, Ramsperger, Kassal and Marcus (RRKM). If these rates are fast compared to all reaction path rates, the primary assumption of RRKM theory is satisfied and RRKM theory is applicable. One aspect of energy transfer that is not well understood is the extent to which collisions induce IVR. Because collisions perturb the partitioning of energy within a molecule they affect the IVR rates. In this work we use classical molecular dynamics simulations to study the collision induced IVR rates and the effect the impact parameter has on these rates for the 1,1,1-trifluoroethane and nitric acid systems. Knowledge of the magnitude of the collision induced IVR rates is important in the IVR theory of Leitner and Wolynes, for example.

Poster Session
7:30 PM-10:00 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster

Division of Physical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006