The formation of heterocoerdianthrone (HCD) following laser pulse photolysis of its endoperoxide (HCDPO) was observed by laser-induced fluorescence. The rise time of HCD was determined to be 7, = 40 &-10 ps. The lifetime of the S,( RT\*) state of HCDPO, from which cycloreversion occurs, was estimate
Picosecond photochemistry: The mechanism of photocycloreversion of aromatic endoperoxides
โ Scribed by K. Jesse; R. Markert; F.J. Comes; R. Schmidt; H.-D. Brauer
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 505 KB
- Volume
- 166
- Category
- Article
- ISSN
- 0009-2614
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โฆ Synopsis
Time-resolved in combination with steady-state experiments reveal that aromatic endoperoxides dissociate in general in IWO steps via a biradical intermediate if excited to upper xu* singlet states. This process is not influenced by solvent. Time constants in the picosecond domain are reported.
๐ SIMILAR VOLUMES
Picosecond measurements show that the photo-fragmentation of anthraccne endoperoxides leading to the anthracene moiety and singlet oxygen does not occur in a single step, but involves a short-lived intermediate. The upper excited state dual bond dissociation kinetics of the endoperoxides of 9,lOdiph
The temperature dependence of the photocycbreversionof the endoperoxide (HCDPO) of heterocoerdianthrone (HCD) yielding HCD and IO2 has been studied. Steady-state experiments show that the quantum efficiency for this process is not influenced by temperature in the wavelength region where the $(mr\*)
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