The first well resolved (I + 1 )-photodissociation spectra of molecular ions are presented. By separating the spectroscopic step (first photon) and the dissociation step (second photon) we could extend the accessible spectral region of CH,I\* and CD31+ considerably. The ions are prepared in the vibr
Resonance Raman spectra of photodissociating CH3I and CD3I in solution
โ Scribed by Frances Markel; Anne B. Myers
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 718 KB
- Volume
- 167
- Category
- Article
- ISSN
- 0009-2614
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โฆ Synopsis
Raman spectra of CHJ and CDJ in hexane, including absolute cross sections for CHJ, have been obtained using 266 nm excitation, on resonance with the directly dissociative 3Q0 state. Both isotopic species exhibit long vibrational progressions in the C-I stretch and its combination bands with the methyl umbrella mode. The relative intensities of the C-I overtones in CHJ are similar in vapor and solution phases, indicating that the early photodissociation dynamics are not greatly altered by solvation. The higher overtone transitions are significantly broadened and shifted to lower frequencies in solution. The absorption spectra and resonance Raman intensities of CHaI have been simulated by parameterizing an uncoupled two-oscillator model in which the C-I stretch is taken as a Morse oscillator in the ground state with an exponential repulsive potential in the excited state.
๐ SIMILAR VOLUMES
We have compared the performance of CF31, CD31, and CH31 in an atomic iodine photodissoctition laser over the pressure range l-200 torr. At pressures below 5 torr, CD31 produces larger energy outputs, while above 5 torr CFJl gives supcrior performance. The crossing of the laser cnergf output versus
The processes that occur subsequent to the absorption of multiple photons by CHsI and CDs1 in the 325-335 nm region have been studied using a single stage time-of-flight mass spectrometer. At the fluences employed, ionization of methyl iodide, at parent resonances that were studied, can compete with
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