Photodissociation dynamics of the phenyl radical via photofragment translational spectroscopy

Journal Article · Sat Aug 21 00:00:00 EDT 2010 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.3473743· OSTI ID:21559901

Negru, Bogdan; Goncher, Scott J; Brunsvold, Amy L; Just, Gabriel M. P.; Park, Dayoung; Neumark, Daniel M ^[1]

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1. Department of Chemistry, University of California, Berkeley, California 94720, USA and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

Photofragment translational spectroscopy was used to study the photodissociation dynamics of the phenyl radical C{sub 6}H{sub 5} at 248 and 193 nm. At 248 nm, the only dissociation products observed were from H atom loss, attributed primarily to H+o-C{sub 6}H{sub 4} (ortho-benzyne). The observed translational energy distribution was consistent with statistical decay on the ground state surface. At 193 nm, dissociation to H+C{sub 6}H{sub 4} and C{sub 4}H{sub 3}+C{sub 2}H{sub 2} was observed. The C{sub 6}H{sub 4} fragment can be either o-C{sub 6}H{sub 4} or l-C{sub 6}H{sub 4} resulting from decyclization of the phenyl ring. The C{sub 4}H{sub 3}+C{sub 2}H{sub 2} products dominate over the two H loss channels. Attempts to reproduce the observed branching ratio by assuming ground state dynamics were unsuccessful. However, these calculations assumed that the C{sub 4}H{sub 3} fragment was n-C{sub 4}H{sub 3}, and better agreement would be expected if the lower energy i-C{sub 4}H{sub 3}+C{sub 2}H{sub 2} channel were included.

• OSTI ID: 21559901
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 7 Vol. 133; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ARYL RADICALS
ATOMS
BRANCHING RATIO
CHEMICAL REACTIONS
DECAY
DECOMPOSITION
DIMENSIONLESS NUMBERS
DISSOCIATION
ENERGY
ENERGY LEVELS
ENERGY SPECTRA
GROUND STATES
KINETICS
ORGANIC COMPOUNDS
PHENYL RADICALS
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
POTENTIAL ENERGY
RADICALS
REACTION KINETICS
SPECTRA
SPECTROSCOPY
SURFACES