The 205 nm photodissociation of ICH{sub 2}CH{sub 2}OH and ICH{sub 2}CH{sub 2}CN

Conference · Fri Dec 31 04:00:00 EST 1993

OSTI ID:141449

Hess, W P; Sapers, S P ^[1]

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1. Pacific Northwest Laboratory, Richland, WA (United States)

The authors study the dissociation of ICH{sub 2}CH{sub 2}OH and ICH{sub 2}CH{sub 2}CN following 205 nm laser excitation and determine the OH and CN product state distributions using LIF (laser induced fluorescence). The OH and CN fragments are likely produced by different dissociation mechanisms. The ground state conformation of ICH{sub 2}CH{sub 2}OH is constrained by an intramolecular hydrogen bond. The primary dissociation of ICH{sub 2}CH{sub 2}OH cleaves the C-I bond and produces CH{sub 2}CH{sub 2}OH in a distribution of internal states, some of which have sufficient energy to undergo secondary, non-photoinduced dissociation to form OH and C{sub 2}H{sub 4}. The OH rotational state distribution is distinctly non-Boltzmann with no OH vibrational excitation detected. The CN rotational state distribution, however, is well fit by a 1300 K Boltzmann distribution with significant vibrational excitation detected. Doppler analysis of the rotational lineshapes is used to determine average speed distributions of the OH and CN fragments. Energetic considerations imply that the CN fragments are formed as a primary rather than a secondary dissociation product. Plausible mechanisms for the two dissociation processes will be discussed.

• OSTI ID: 141449
• Report Number(s): CONF-930304--
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
CHEMICAL BONDS
CYANIDES
DISSOCIATION
FLUORESCENCE SPECTROSCOPY
HYDROXYL RADICALS
ORGANIC IODINE COMPOUNDS
PHOTOCHEMICAL REACTIONS