| Abstract
| - The electron-transfer process of a first generation dendrimer with a triphenylamine core substitutedwith one peryleneimide chromophore at the rim (N1P1) was investigated by steady-state and time-resolvedspectroscopic techniques in two different solvents of medium and low polarity. Single photon countingexperiments showed a fast charge separation and a thermally activated back reaction, which is uncommonfor a polyaryl bridge or long-distance through-space electron transfer. The four exponential fluorescencedecay can be traced to the presence of two subsets of molecules, which are constitutional isomers ofN1P1. Although formally N1P1 resembles a donor-bridge-acceptor compound, detailed analysis of the datashows that the electron transfer occurs by a through-space mechanism. This amine core dendrimer haspeculiar and unique characteristics resulting in the observation of efficient back transfer and delayedperyleneimide fluorescence in diethyl ether at 293 K and very long-lived charge recombination luminescenceat 77 K.
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