| Autor: |
Andreas Herrmann, Tanja Weil, M. Van der Auweraer, G. De Belder, Marc Lor, Johan Hofkens, S. Jordens, R. De, Mircea Cotlet, Gerd Schweitzer, F. C. De Schryver, Klaus Müllen |
| Přispěvatelé: |
Zernike Institute for Advanced Materials, Nanotechnology and Biophysics in Medicine (NANOBIOMED) |
| Jazyk: |
angličtina |
| Rok vydání: |
2002 |
| Předmět: |
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| Zdroj: |
The Journal of Physical Chemistry. A: Molecules, Spectroscopy, Kinetics, Environment, & General Theory, 106(10), 2083-2090. AMER CHEMICAL SOC |
| ISSN: |
1520-5215 |
| Popis: |
Intramolecular kinetic processes in a series of second-generation polyphenyl dendrimers with multiple peryleneimide chromophores attached to the para position of the outer phenyl ring were investigated by steady-state and femtosecond to nanosecond time-resolved fluorescence spectroscopy. The results obtained were compared to the ones of the corresponding first-generation dendrimer series. The energy-hopping rate constant, khopp, observed from anisotropy decay times was found to be 5 times smaller than that of the first-generation series and scales well with the difference in average distance between the chromophores. In addition to the processes observed in first-generation dendrimers in the ultrafast time domain by fluorescence up-conversion, a second annihilation process is found in the second-generation multichromophoric dendrimer. The observation of two singlet-singlet annihilation processes in this compound can be explained by the presence of a mixture of constitutional isomers leading to a broader distribution of distances between neighboring chromophores compared to first-generation multichromophoric dendrimers. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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