| 초록 |
Donor–π–acceptor dyads (D–π–A (1) and D–π–Si–π–A (2)) were prepared to elucidate the effect of π-conjugation on photoinduced electron transfer (PET) and intramolecular charge transfer (ICT) processes,. In these molecules, triazine and carbazole moieties acted as the electron acceptor and doner, respectively. The photoluminescence of 1 red-shifted with increase of solvent polarity. In the excited state of 1, the π-conjugation acted as the linker for charge transfer (Dδ+-π-Aδ-) between the donor and acceptor moieties. The changing of a large dipole moment between the ground and excited states was determined using the Lippert-Mataga plot. In case of 2, the π-conjugation is disconnected by a Si-atom in the linker. The fluorescence of 2 showed weak dual-emission: a short-wavelength emission at around 350 nm arising from the monomeric species and a long-wavelength one assigned to the emission from an intramolecular exciplex between the donor and acceptor moieties. |
