IR diode laser study of vibrational energy distribution in CO/sub 2/ produced by UV excimer laser photofragmentation of pyruvic acid

Journal Article · Thu Oct 15 00:00:00 EDT 1987 · J. Chem. Phys.; (United States)

OSTI ID:6034339

O'Neill, J A; Kreutz, T G; Flynn, G W

Time domain absorption spectroscopy using a tunable, infrared diode laser has been used to monitor the vibrational excitation of CO/sub 2/ produced in the 193 nm excimer laser photolysis of gas phase pyruvic acid (CH/sub 3/COCOOH). Nascent vibrational populations were measured in the following ten vibrational states of CO/sub 2/: 00/sup 0/0, 01/sup 1/0, 02/sup 2/0, 03/sup 3/0, 04/sup 4/0, 00/sup 0/1, 00/sup 0/2, 00/sup 0/3, 01/sup 1/1, and 02/sup 2/1. Approximately 97% of the CO/sub 2/ photoproduct is observed to be directly formed in the vibrational ground state. The remaining molecules are formed with a significant degree of vibrational excitation, having mode temperatures T(..nu../sub 2/) = 1800 +- 150 K, T(..nu../sub 3/) = 3700 +- 1000 K, T(..nu../sub 2/+..nu../sub 3/) = 2000 +- 400 K. The present experimental data suggest that the 193 nm photolysis may proceed through more than a single dissociation channel and involve a number of different photofragments.

• Research Organization: Department of Chemistry and Columbia Radiation Laboratory, Columbia University, New York, New York 10027
• OSTI ID: 6034339
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 87:8; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBOXYLIC ACIDS
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
DISTRIBUTION
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
KETO ACIDS
MONITORING
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
PYRUVIC ACID
VIBRATIONAL STATES