Formation of the diphenyl molecule in the crossed beam reaction of phenyl radicals with benzene

Journal Article · Thu Feb 28 04:00:00 EST 2008 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.2834221· OSTI ID:21103855

Fangtong, Zhang; Xibin, Gu; Kaiser, Ralf I ^[1]

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1. Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822 (United States)

The chemical dynamics to form the D5-diphenyl molecule, C{sub 6}H{sub 5}C{sub 6}D{sub 5}, via the neutral-neutral reaction of phenyl radicals (C{sub 6}H{sub 5}) with D6-benzene (C{sub 6}D{sub 6}), was investigated in a crossed molecular beams experiment at a collision energy of 185 kJ mol{sup -1}. The laboratory angular distribution and time-of-flight spectra of the C{sub 6}H{sub 5}C{sub 6}D{sub 5} product were recorded at mass to charge m/z of 159. Forward-convolution fitting of our data reveals that the reaction dynamics are governed by an initial addition of the phenyl radical to the {pi} electron density of the D6-benzene molecule yielding a short-lived C{sub 6}H{sub 5}C{sub 6}D{sub 6} collision complex. The latter undergoes atomic deuterium elimination via a tight exit transition state located about 30 kJ mol{sup -1} above the separated reactants; the overall reaction to form D5-diphenyl from phenyl and D6-benzene was found to be weakly exoergic. The explicit identification of the D5-biphenyl molecules suggests that in high temperature combustion flames, a diphenyl molecule can be formed via a single collision event between a phenyl radical and a benzene molecule.

• OSTI ID: 21103855
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 8 Vol. 128; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR DISTRIBUTION
BENZENE
BIPHENYL
COLLIDING BEAMS
COLLISIONS
COMBUSTION
DEUTERIUM
DISSOCIATION
MOLECULAR BEAMS
PHENYL RADICALS
TIME-OF-FLIGHT METHOD