Chromophore inducibility

Although the anthracene units are coplanar, there is no electronic interaction between the chromophores in the crystal. Although such an arrangement makes this class of anthracene derivatives unusable for use in applications requiring efficient charge transport (organic transistors or solar cells), the insulation of the fluorescent chromophore induced by this method may make these materials useful as emitters in OLEDs. 

Absorption of a photon by the chromophore induces primary photoreaction, followed by conformational changes of protein, and eventually activates transducin. This is called the bleaching process because rhodopsin loses its color. To investigate the primary photoreaction processes in rhodopsin, two spectroscopic approaches have been applied low-temperature and time-resolved spectroscopies... 

The photomorphogenic control functions are triggered by trans cis and ds—> trans double-bond isomerizations of the chromophore induced by red (r) and far-red ft) light, respectively. The Pjj. photocycle is illustrated in Scheme 8.6. 

Data on the excited state properties of meso and racemic A6 are reported by De Schryver et al. (1982b), Masuhara et al. (1983), Evers et al. (1983) and Vandendriessche et al. (1984). The Sq absorption spectra of meso A6, racemic A6 and NIPCz are identical (De Schryver et al., 1982b). This suggests that in meso A6 the population of TT is low and that in the TT conformation in racemic A6 the partial overlap of the chromophores induces a little or no interaction. 

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