Examples from the field of dendritic molecules

The photophysical effects and mechanisms described in general terms in the above sections will now be illustrated with the aid of findings and interpretations from the world of dendrimers. Since straightforward luminescence effects are also mentioned elsewhere in this book in the context of syntheses (Chapter 2) and the individual types of compounds (Chapter 4) and are, moreover, considered as part of more complex events in Section 5.2, just a few characteristic examples of fluorescence and phosphorescence of dendrimers will be presented The adjacency of many groups in a molecule may lead to the occurrence of complex processes, which sometimes make it difficult to draw precise conclusions, but may sometimes also be useful and amenable to optimisation for various applications. 

The dendrimer of mixed POPAM/Frechet type shown in Fig. 5.5 formally bears several types of fluorophores in three shells naphthyl units on the periphery two layers with dimethoxybenzene character further inside and finally the strongly fluorescing dansyl groups - adding up to a total of 64 luminophoric moieties. Incident UV radiation interacts first with the naphthyl groups, which 

Addition to such fluorescent dendrimers of non-fluorescing guest compounds capable of interacting with the hetero atoms of the dendrimer - Cu2+ or Co2+ ions in the simplest case - leads to (partial) quenching of fluorescence. A specific example of such behaviour will be found in Section 6.23.3. 

Another example of this type of interaction is given in Section 3.2.1 (Fig. 3.14). 

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