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8360787 
Journal Article 
Determination of rate constants of 1O2 consumption by 1O2 acceptors in weakly deactivating solvents 
Opriel, U; Seikel, K; Schmidt, R; Brauer, HD 
1989 
Yes 
Journal of Photochemistry and Photobiology A: Chemistry
ISSN: 1010-6030
EISSN: 1873-2666 
49 
3 
299-309 
English 
The rate constants kdobs of 1O2 consumption were measured directly in CS2 for eight 1O2 acceptors using the time-resolved technique. The values obtained agree well with the values of k1obs in toluene and benzene which were estimated indirectly from the reactivity parameter β previously determined in self-sensitized or sensitized photo-oxygenation experiments. Only the measurements of the self-sensitized photo-oxygenation of 9,10-diphenyl-anthracene (DPA) and 9,10-dimethylanthracene (DMA) in CS2 yield values of β which are consistent with a long lifetime of 1O2 of τΔ = 34 ms in this solvent. The determination of β from measurements of the self-sensitized photo-oxygenation in CS2 results in β values which are too high for the rest of the 1O2 acceptors, indicating that the lifetime of 1O2 in CS2 is strongly reduced in these experiments. The same behaviour is observed for the self-sensitized photo-oxygenation of DPA and DMA in Freon 113. © 1989.