| Autor: |
Alfano, Joseph C., Martinez, Selso J., Levy, Donald H. |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 2/15/1991, Vol. 94 Issue 4, p2475, 7p |
| Abstrakt: |
Time-resolved measurements have been performed on seven vibronic levels of the S1 states of 3-amino-s-tetrazine (AT) and nine vibronic levels of 3-amino–6-methyl–s-tetrazine (AMT) ranging from 0 to 1907 cm-1 of excess vibrational energy. The resulting fluorescence lifetimes were found to range from 219 to 59 ns, and monotonically decreased with increasing excess energy. We have estimated the nonradiative rates and fluorescence quantum yields for these 16 levels by two different methods, which give reasonable agreement. These show that AT and AMT have nonradiative rates around 106–107 s-1, and very high fluorescence quantum yields, ranging from 0.07 to 0.29. This stands in contrast to s-tetrazine, which has a fluorescence lifetime of 800 ps, a nonradiative rate of 1.25×109s-1, and a fluoresence quantum yield of 0.000 94. This difference in the photophysical properties of AT and AMT relative to tetrazine is discussed in terms of the extensive work done on the photophysics and substituent effects of other azabenzenes, particularly pyridine. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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