Cyanine Dyes: Fine Structures in Their Absorption Spectra
نویسنده
چکیده
Absorption spectra were studied for two series of 3 cyanine dyes with varying length of conjugated hydrocarbon chains. Fine sturctures in absortpiton spectra were analyzed to determine its concentraion dependence as the concentraion of dyes were changed from 10 –8 M to 10 –4 M. In all 6 dyes studied, ratios of minor peaks to the major peak remained constant within the experiemntal error. These results indicate that the origin of the absorption fine structure is due to the electronic coupling, an intramolecular process, rather than the aggragates formation, an intermolecular process.
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