ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The reactivity of singlet oxygen (O2(1Δg)) with edta and its metal complexes with Al3+, Cu2+, Fe3+, and Mn2+ was investigated. The emission of singlet oxygen at 1270 nm in D2O was measured in order to determine the quenching efficiency of edta and edta-metal complexes for different metal/edta ratios. The sum of the rate constant (kr + kq) of the chemical reaction between singlet oxygen and the acceptor (kr) and of the physical quenching of singlet oxygen by the acceptor (kq) was obtained by a Stern-Volmer analysis. Measurements of the oxygen consumption in H2O were used to determine quantum yields of the sensitized photooxidation, and the combined results of these experiments allowed the determination of kr and kq separately. A strong isotope effect was observed between the deuterated and the hydrogenated solvents. This effect was shown to be independent of the analytical procedure used. The isotope effect, as well as the reactivity of edta and its metal complexes, depend markedly on the complexed metal ion.
Additional Material:
5 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19940770325
Permalink