Dynamics of O(3P) Reactions with Gaseous, Liquid, and Solid Hydrocarbons
Abstract
This final report describes the initial two phases of the overall project. In the first phase, accurate barriers and energetics were calculated for 7 reactions involved in O(3P) oxidation of hydrocarbons. This was done by MRCI/CASSCF ab initio calculations with cc-pVTZ and cc-pVQZ basis sets and extrapolation to the complete basis set limit. For collisions of high- energy O(3P) atoms with hydrocarbons, the radical products contain sufficient internal energy to undergo unimolecular decomposition. Tests showed that PMP2//UMP2/cc-pVTZ gives accurate energies and transition state properties for these reactions, and this information was also used to characterize the potential energy surface for hydrocarbon oxidation. In the second phase, the PM3 semiempirical quantum chemistry method, with a UHF wavefunction, was modified and parameterized with specific reaction parameters (SRPs) to fit the ab initio barriers, reactions energies, and geometries determined in phase 1. The resulting method, PM3-SRP, gives a good fit to the ab initio data. The PM3-SRP method was tested in a trajectory study of the O(3P) + C2H6 > OH + C2H5 reaction dynamics. The results agree with experiment.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 10, 2004
- Accession Number
- ADA428076
Entities
People
- William L Hase
Organizations
- Wayne State University