Spectral distribution of CO/sub 2/ vibrational states produced by collisions with fast hydrogen atoms from laser photolysis of HBr
193 nm photofragmentation of HBr molecules in HBr/CO/sub 2/ mixtures produces energetic (approx.2.5 eV) hydrogen atoms which vibrationally excite CO/sub 2/ molecules via an inelastic translation-vibration/rotation (T-V/R) energy exchange process. Prompt infrared emission in the 4.3 ..mu..m region has been wavelength resolved, and the spectral energy distribution associated with the excited CO/sub 2/ product was measured. The emission profile is strongly red shifted from the spectral region of the ..nu../sub 3/ (00/sup 0/1--00/sup 0/0) fundamental transition indicating that these energetic collisions preferentially produce combination and overtone levels with oscillator strength in the 4.3 ..mu..m region. Cold gas filter studies show that significant emission originates from CO/sub 2/ bend--stretch excitation compared to pure stretching excitation. Approximately 15% of the emission is due to the 01/sup 1/1--01/sup 1/0 transition while the remaining fluorescence has contributions from levels above the 01/sup 1/1 state. The data are in qualitative agreement with theoretical calculations on O/CO/sub 2/ collisions employing either quasiclassical trajectory or infinite order sudden methods, but do not agree with predictions based upon either (harmonic oscillator) breathing sphere theory or statistical theory.
- Research Organization:
- Department of Chemistry and Columbia Radiation Laboratory, Columbia University, New York, New York 10027
- OSTI ID:
- 5636609
- Journal Information:
- J. Chem. Phys.; (United States), Vol. 78:6
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CARBON DIOXIDE
ATOM-MOLECULE COLLISIONS
INFRARED SPECTRA
VIBRATIONAL STATES
HYDROGEN
EMISSION SPECTRA
ENERGY TRANSFER
HYDROBROMIC ACID
PHOTOLYSIS
ATOM COLLISIONS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
COLLISIONS
DECOMPOSITION
ELEMENTS
ENERGY LEVELS
EXCITED STATES
HYDROGEN COMPOUNDS
INORGANIC ACIDS
MOLECULE COLLISIONS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
SPECTRA
640304* - Atomic
Molecular & Chemical Physics- Collision Phenomena