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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
The benzene+OH potential energy surface: intermediates and transition states
David S Hollman1, Andrew C Simmonett, Henry F Schaefer
1The Center for Computational Quantum Chemistry, The University of Georgia, GA, USA.
Physical Chemistry Chemical Physics : PCCP
|November 25, 2010
Summary
This study details the benzene-hydroxyl radical interaction using quantum mechanics, revealing a low energy barrier for hydrogen abstraction. Computational chemistry accurately models the complexation energies of the benzene-hydroxyl radical and phenyl radical-water complexes.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Chemical Physics
Background:
- The interaction between aromatic compounds and radicals is crucial for combustion and atmospheric chemistry.
- Understanding the benzene-hydroxyl radical system provides insights into oxidation processes.
Purpose of the Study:
- To investigate the potential energy surface for benzene and hydroxyl radical interactions.
- To determine the energetics of complex formation and the hydrogen abstraction pathway.
Main Methods:
- Utilized quantum mechanical methods for theoretical calculations.
- Employed density functional theory and perturbation theory for geometric optimizations.
- Refined energy calculations using coupled cluster singles and doubles with perturbative triples [CCSD(T)] extrapolated to the complete basis set limit.
Main Results:
- Calculated complexation energies for benzene-hydroxyl radical and phenyl radical-water complexes.
- Determined the energy barrier for hydrogen abstraction from benzene by hydroxyl radical.
- Provided accurate energetic values for key stationary points on the potential energy surface.
Conclusions:
- The study provides a detailed computational analysis of the benzene-hydroxyl radical interaction.
- The calculated low barrier suggests facile hydrogen abstraction under relevant conditions.
- The findings contribute to a fundamental understanding of radical-aromatic interactions in chemical systems.
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