Adiabatic structural relaxation in heterocyclic nitrogen-containing cations
Autor: | M. I. Knyazhansky, V. A. Kharlanov, Ya.R. Tymiansky |
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Rok vydání: | 1998 |
Předmět: |
genetic structures
General Chemical Engineering Analytical chemistry General Physics and Astronomy General Chemistry Fluorescence Fluorescence spectroscopy chemistry.chemical_compound symbols.namesake chemistry Atomic electron transition Chemical physics Stokes shift symbols Pyridinium Solvent effects Adiabatic process Polarization (electrochemistry) |
Zdroj: | Journal of Photochemistry and Photobiology A: Chemistry. 118:151-156 |
ISSN: | 1010-6030 |
DOI: | 10.1016/s1010-6030(98)00377-3 |
Popis: | The detailed studies of the 2,4,6-(N-alkyl)triarylsubstituted pyridinium cations I as well as the large series of the model structures have been carried out by absorption, fluorescent and polarization methods in the solvents of various polarity and viscosity at different temperatures. The localizations of the lowest electron transitions are determined. It is shown that the fluorescence with anomalous Stokes shift (ASS-fluorescence) arises owing to the adiabatic structural relaxation (ASR) with the formation of the flattened (but not twisted) structure. The advantages of I as the objects for ASR study are discussed. The crude determination of the ASR kinetic parameters has been conducted. A data assume that the ASS fluorescence quantum yields of the cations I are conditioned mainly by deactivation processes in the final flattened structure. |
Databáze: | OpenAIRE |
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