IR diode laser study of vibrational energy distribution in CO2 produced by UV excimer laser photofragmentation of pyruvic acid
Abstract
Time domain absorption spectroscopy using a tunable, infrared diode laser has been used to monitor the vibrational excitation of CO2 produced in the 193 nm excimer laser photolysis of gas phase pyruvic acid (CH3COCOOH). Nascent vibrational populations were measured in the following ten vibrational states of CO2: 0000, 0110, 0220, 0330, 0440, 0001, 0002, 0003, 0111, and 0221. Approximately 97% of the CO2 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(ν2)=1800±150 K, T(ν3)=3700 ±1000 K, T(ν2+ν3)=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.
- Publication:
-
Journal of Chemical Physics
- Pub Date:
- October 1987
- DOI:
- 10.1063/1.453711
- Bibcode:
- 1987JChPh..87.4598O
- Keywords:
-
- Carbon Dioxide;
- Energy Distribution;
- Excimer Lasers;
- Photodissociation;
- Vibrational Spectra;
- Absorption Spectroscopy;
- Infrared Lasers;
- Semiconductor Diodes;
- Ultraviolet Lasers;
- Atomic and Molecular Physics