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Published on: July 27, 2018
Photodissociation dynamics of benzoic acid
Yuri A Dyakov1, Arnab Bagchi, Yuan T Lee
1Institute of Atomic and Molecular Sciences, Academia Sinica, P.O. Box 23-166, Taipei 10617, Taiwan.
The Journal of Chemical Physics
|January 19, 2010
Summary
Researchers studied benzoic acid photodissociation using ion imaging. Different dissociation pathways were observed at 193 nm and 248 nm, suggesting complex electronic state involvement in the reaction.
Area of Science:
- Photochemistry
- Chemical Kinetics
- Molecular Spectroscopy
Background:
- Benzoic acid is an aromatic carboxylic acid with significant applications.
- Understanding its photodissociation is crucial for atmospheric chemistry and reaction dynamics.
Purpose of the Study:
- To investigate the photodissociation pathways of benzoic acid at 193 nm and 248 nm.
- To elucidate the electronic states involved in the dissociation process.
Main Methods:
- Multimass ion imaging techniques were employed to study the photodissociation.
- Experimental data were compared with ab initio calculations and Rice-Ramsperger-Kassel-Marcus (RRKM) theory.
Main Results:
- Three distinct dissociation channels were identified at 193 nm: C(6)H(5)COOH → C(6)H(5) + COOH, C(6)H(5)COOH → C(6)H(5)CO + OH, and C(6)H(5)COOH → C(6)H(6) + CO(2).
- Only two channels (C(6)H(5)CO + OH and C(6)H(6) + CO(2)) were observed at 248 nm.
- Analysis of ion intensities, photofragment translational energy distributions, and branching ratios indicated dissociation occurs across multiple electronic states.
Conclusions:
- The photodissociation of benzoic acid is a complex process influenced by various electronic states.
- Wavelength-dependent studies reveal distinct reaction dynamics at 193 nm and 248 nm.
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