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Autori: Jhony Orbulescu, Péter Kele, András Kotschy and Roger M. Leblanc*
Editorial: The Royal Society of Chemistry, Journal of Materials Chemistry, 15 (30), p.3084 - 308, 2005.
This paper focuses on the examination of the Photoinduced Electron Transfer (PET) and Internal Charge Transfer (ICT) for two coumarin derivatives, namely 7-methoxycoumarin-4-methyl-1-aza-18-crown-6 and di(7-methoxycoumarin-4-methyl)-1,10-diaza-18-crown-6. The spectroscopic properties were investigated by UV-Vis and fluorescence spectroscopies. It was found that a dual mechanism explains the fluorescence enhancement and blue shift in the presence of a cationic species, namely saxitoxin. The ICT was elucidated by the polarity effect of methanol on the fluorescence of di(7-methoxycoumarin-4-methyl)-1,10-diaza-18-crown-6.
Cuvinte cheie: PET, ICT, fluorescence, coumarins