The use of a spin-forbidden transition enhancer as dimethylmercury allows one to measure phoqhorescencc spectra in a fluid medium at room temperature. As an example, the T1 + So radiative transition ofoct~hcficcne.
Room temperature phosphorescence of aromatic hydrocarbons in aqueous micellar solutions
โ Scribed by K. Kalyanasundaram; F. Grieser; J.K. Thomas
- Publisher
- Elsevier Science
- Year
- 1977
- Tongue
- English
- Weight
- 451 KB
- Volume
- 51
- Category
- Article
- ISSN
- 0009-2614
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โฆ Synopsis
The phosphorescence spectra of several simple arenes, pyrene, naphthahne, biphenyl and their bfiminated derivatives have been observed in aqueous micellar solutions at room temperature. The success of these experiments is due to the protective screening of the arene triplet state by solubilization in the micclles. Impurities in the aqueous phase are thus excluded from the excited arene. Small traces of oxygen efficiently remove the phosphorescence as oxygen readily penetrates into the micelle to quench the arene triplet. Hydrophillic quenchers such as Cu **and Ti+also reduce the lifetime of the phosphorescence. In anionic micelles these quenchers are located at the surface of the micelle and efficient quenching takes place at the lipid water interface. Cupric ions reduce the lifetime and yield of phosphorescence, while Ti+ionh reduce the lifetime but also enhance the rate of emission of the phosphorescence via heavy atom spin orbit coupling. The technique and data are relevant to the nleasurement of kinetic parameters in micelles and membranes.
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