Decay of fluorescence from single vibronic states of SO2

✍ Scribed by Man-Him Hui; Stuart A. Rice

• Publisher: Elsevier Science
• Year: 1972
• Tongue: English
• Weight: 514 KB
• Volume: 17
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(72)85083-8

✦ Synopsis

The fluoresccncc from ten vibronic states in the 2300 to 2100 A absorption region of SO2 has been studied. A sharp drop in fluorescence quantum yield and fluorescence lifetime for wavelengths shorter than 2206 A is a:t:ibuted to the dissociation of SO,. 'Ihe quantum yield of fluorescence in the spectral region where there is no dissociation is unity at zero pressure, within our experimental error. We observed neither anomalously long lifetimes of lIuoresccnce, nor non-exponential decay of fluorescence, indicating that there is weak coupling between the state(s) studied and other states.

Comparison of our experimental data with calculations based on RRXM theory suggests that energy randomization is not complete before dissociation, and that coupling between the symmetric bending mode and tic asymmetric stretching mode is wry weak.