This item still needs to be validated !
Title: Femtosecond fluorescence upconversion study of rigid dendrimers containing peryleneimide chromophores at the rim
Authors: De Belder, Gino ×
Jordens, Sven
Lor, Marc
Schweitzer, Gerd
De, Rina
Weil, T
Herrmann, A
Wiesler, UK
Mullen, K
De Schryver, Frans #
Issue Date: Jan-2001
Publisher: Elsevier science sa
Series Title: Journal of photochemistry and photobiology a-chemistry vol:145 issue:1-2 pages:61-70
Abstract: The kinetics of a newly synthesized series of a first generation of polyphenylene dendrimers in which one phenyl in a dendritic arm was para-substituted by a peryleneimide chromophore are reported. One such peryleneimide chromophore is attached to 1, 3 or 4 arms. The results are compared to a series of polyphenylene dendritic compounds, which are identical except for the substitution at a meta-position of a phenyl ring. The para-substitution yields a better spatial definition of the peryleneimide units relative to one another and the influence of this aspect on the kinetics is studied. Four different kinetic components were resolved for both groups of dendrimers. An ultra-short component varying from 500 fs to 2 ps and attributed to intramolecular vibrational redistribution (IVR) is identical for both series. The decay time of a second component, which is comprized of the vibrational relaxation and a singlet-singlet annihilation process observed in both substituted dendrimer series, is shorter in the para-substituted dendrimers compared to the meta-substituted ones. It is also shown that the annihilation process, which is only present in the multi-chromophoric compounds of both the series and resolved with an excitation energy dependent study, has definitely a larger contribution in the partial amplitudes for the para-substituted compounds. This is related to the relative orientation of the transition dipoles of the chromophores in both the series. (C) 2001 Elsevier Science B.V. All lights reserved.
ISSN: 1010-6030
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Molecular Imaging and Photonics
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science