Abstract
Photoinduced inter- and intramolecular electron transfer reactions of methylene-linked (n) carbazole and terephthalic acid methyl ester (abbreviated as D-(n)-A, n=4 and 12) have been examined by using external electromodulated fluorescence spectroscopy and photocurrent measurement, which allow one to obtain information about the Stark shift and the efficiency of fluorescence quenching as well as photocarrier generation induced by an electric field. The action spectra of the photocurrent could be successfully measured at various concentrations in the absorption region of carbazole (240-365 nm). The obtained action spectra agree well with the simultaneously measured fluorescence excitation spectra, indicating that photocarrier generation occurs following the relaxations including internal conversion to Si and excitation energy migration among carbazole chromophores. Furthermore, the efficiency of photocarrier generation of D-(12)-A is higher than that of D-(4)-A, indicating that an intramolecular recombination process plays an important role in charge recombination of a photogenerated ion-pair state.
| Original language | English |
|---|---|
| Pages (from-to) | 483-488 |
| Number of pages | 6 |
| Journal | Molecular Crystals and Liquid Crystals Science and Technology Section A: Molecular Crystals and Liquid Crystals |
| Volume | 315 |
| DOIs | |
| State | Published - 30 Apr 1998 |
| Event | Proceedings of the 1998 TAPPI Metered Size Press Forum - New Orleans, LA, USA Duration: 30 Apr 1998 → 2 May 1998 |
Keywords
- Charge recombination
- Electric field effects
- Exciplex fluorescence quenching
- Intramolecular electron transfer
- Photocarrier generation