Unimolecular reaction dynamics of well characterized ionic reactions. Final report, 1993--1997
The dissociation dynamics of well characterized and energy selected ions have been investigated by photoelectron photoion coincidence (PEPICO) spectrometry. A number of ions have been found which dissociate in competition with isomerization and which thus lead to multi-component decay rates. The dissociation dynamics on such complex potential energy surfaces are common for many free radical reactions, including some of importance to combustion processes. Individual reaction rates for isomerization and dissociation have been extracted from the data. In addition, all rates have been successfully modeled with the RRKM theory in combination with ab initio molecular orbital calculations. The dissociation dynamics of a dimer ion system has been studied on the UNC PEPICO apparatus as well as at the Chemical Dynamics Beam line of the ALS. This proof of principle experiment shows that it is possible to investigate such systems and to determine the heats of formation of free radicals by this approach. Finally, a dissociation involving a loose transition state with no exit barrier has been successfully modeled with a simplified version of the variational transition state theory (VTST). The aim of all of these studies is to develop protocols for modeling moderately complex unimolecular reactions with simple models.
- Research Organization:
- Univ. of North Carolina, Dept. of Chemistry, Chapel Hill, NC (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research, Washington, DC (United States)
- DOE Contract Number:
- FG02-88ER13950
- OSTI ID:
- 290882
- Report Number(s):
- DOE/ER/13950-T4; ON: DE99001144; TRN: AHC29901%%87
- Resource Relation:
- Other Information: PBD: [1997]
- Country of Publication:
- United States
- Language:
- English
Similar Records
Ab Initio Unimolecular Reaction Kinetics of CH2C(=)OCH3 and CH3C(=O)OCH2 Radicals
Transition state structures and angular momentum effects in the dissociation dynamics of energy-selected C[sub 4]H[sub 8][sup +] ions