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Published on: April 19, 2019
Cycle formation from acetylene addition on C4H3 radicals
Xavier Lories1, Jacques Vandooren, Daniel Peeters
1Laboratoire de Chimie Quantique, Université catholique de Louvain, Département de Chimie, Bâtiment Lavoisier, Place Louis Pasteur, 1, B-1348 Louvain-la-Neuve, Belgium.
This study investigates acetylene addition reactions on hydrocarbon radicals. New cyclization pathways and dehydro-fulvene radical formation were identified as energetically competitive routes.
Area of Science:
- Combustion chemistry
- Theoretical chemical kinetics
Background:
- Acetylene addition to hydrocarbon radicals is crucial in combustion processes.
- Understanding reaction pathways is key to predicting combustion behavior.
Purpose of the Study:
- To investigate reaction mechanisms of acetylene addition to i- and n-C(4)H(3) radicals.
- To identify and analyze novel cyclization and decomposition pathways.
- To calculate rate constants for these reactions.
Main Methods:
- Modified G3B3 computational method for electronic structure calculations.
- Conventional Transition State Theory (CTST) for rate constant determination.
Main Results:
- Identified energetically competitive cyclization steps for the first time.
- Dehydro-fulvene radical formation is competitive with phenyl radical formation for n-C(4)H(3) + C(2)H(2).
- 6-dehydrofulvene formation is competitive with ortho-benzyne + H decomposition.
Conclusions:
- The study reveals new reaction pathways for acetylene addition to C(4)H(3) radicals.
- Dehydro-fulvene formation represents a significant alternative to phenyl radical pathways.
- Calculated rate constants provide valuable data for combustion modeling.
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