The Journal of Chemical Physics · 1988 · 19 citations · 26 references
Natural SciencesChemistryPhysicsChemical KineticsQuantum ChemistrySpectroscopyElectronic Excited StatesFluorescence SpectroscopyLaser SpectroscopyMolecular Excited StatesOptical SpectroscopyPhotochemistryDecay RatesExcited State QuenchingExcited-state LifetimeFluorescence Lifetime MeasurementsLaser-induced FluorescenceLaser-induced Fluorescence SpectroscopyRadiative Decay RateVibrational Energy Levels
The laser-induced fluorescence technique has been employed to study the first excited electronic state à 2A1 of CH3O. Vibrational levels v′3 =0–7 of the à state were excited and fluorescence decay rates were measured. Compared to a value 2.2±0.2 μs at v3=0, a significant decrease of decay rate was found at 277.6 nm (0.89 μs, v′3=7). Excitation to higher levels further reduced the lifetime. The predissociation threshold was estimated to be slightly above 276 nm (36 220 cm−1). The electronic quenching rates of the à state (v′=0–2) by CH3OH, O2, NO2, and N2 have also been determined and are compared with those of OH in the à state.
26