| 초록 |
The intramolecular photoinduced electron transfer (PET) processes of three bis(4-arylphenylamino benzo)-ortho-carboranes (ArCbAr, Ar=phenyl (Ph), naphthyl (Np) and pyrenyl (Py)) triads were investigated in CH2Cl2 and n-hexane using the femtosecond time-resolved transient absorption (TA) spectroscopic technique. In CH2Cl2, the transient S1-Sn absorption band of 1ArCbAr* was observed at short delay times. Concomitant with the decay of 1ArCbAr*, the TA bands for cation radical species were detected at around 700 nm for Ph•+, 650 nm for Np•+, and 580 nm Py•+. At the same time, the TA band of the carborane anion radical (Cb•-) was observed at around 430 nm. This implies that the intramolecular PET process occurs from the 1ArCbAr* state. The TA bands of the cationic and anionic radical species can be assigned by comparison to the absorption spectra of an electrochemically generated radical species. |
