Photodissociation study of CH3Br in the first continuum
J. Chem. Phys. 108, 5742 (1998); doi:10.1063/1.475984
Issue Date: 8 April 1998
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The photolysis of CH3Br is studied in the energy region of the A band between 4.94 and 5.76 eV using ion imaging. Velocity distributions for both the bromine-atom and methyl-radical photofragments are determined. Our results indicate that transitions to the 3Q0 and 3Q1 states dominate the absorption cross section and the partial cross section to each state is determined. The [Br*]/[Br] branching ratio is found to be strongly dependent on the excitation energy varying between 0.6 and 1.5. Both the bromine-atom and the methyl-radical translational energy distributions suggest that the vibrational distribution in the nascent CH3 is nonstatistical with appreciable excitation in the v2 umbrella mode. The lifetime of the A band is estimated at
= 120 ± 40 fs. ©1998 American Institute of Physics.
= 120 ± 40 fs. ©1998 American Institute of Physics.
| History: | Received 20 October 1997; accepted 6 January 1998 |
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http://link.aip.org/link/?JCPSA6/108/5742/1 |
KEYWORDS and PACS
- 33.80.Gj
Molecular properties and interactions with photons Photon interactions with molecules Diffuse spectra; predissociation, photodissociation - 82.50.Fv
Physical chemistry Photochemistry and radiation chemistry Photolysis, photodissociation, and photoionization by infrared, visible, and ultraviolet radiation - YEAR: 1998
RELATED DATABASES
PUBLICATION DATA
0021-9606 (print)
1089-7690 (online)
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