کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9605630 | 44171 | 2005 | 10 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Mechanism of the excited singlet and triplet states quenching by molecular oxygen in acetonitrile
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Rate constants for quenching by molecular oxygen of excited singlet and triplet states, kqS and kqT, respectively, of some aromatic hydrocarbons in acetonitrile are reported. The fraction of excited singlet states quenched by oxygen which result in triplet states, fTS, are in the range of 0.25-0.85. The efficiencies of singlet oxygen production during oxygen quenching of the excited singlet and triplet states, fÎS and fÎT, respectively, were also measured. Values of fÎS were shown to be 0.28 ± 0.05 for 1,2;5,6-dibenzanthracene, pyrene, fluoranthene, 1,11-benzoperlyene and perlyene while values of fÎT cover the range of 0.25-1.0. Combination of the total quenching rate constants with the fractional efficiencies allows separate net quenching rate constants to be obtained for the various oxygen quenching pathways. Factors governing the production of singlet oxygen with different efficiencies during quenching of both excited singlet and triplet states by oxygen are discussed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Photochemistry and Photobiology A: Chemistry - Volume 172, Issue 2, 31 May 2005, Pages 170-179
Journal: Journal of Photochemistry and Photobiology A: Chemistry - Volume 172, Issue 2, 31 May 2005, Pages 170-179
نویسندگان
Ayman A. Abdel-Shafi, David R. Worrall,