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| Type |
Poster Presentation |
| Area |
Industrial Chemistry |
| Room No. |
Exhibition Hall 2+3 |
| Time |
10월 20일 (금요일) 13:00~14:30 |
| Code |
IND.P-74 |
| Subject |
Important Role on Intermolecular Charge Transfer and Photoinduced Electron Transfer by π-conjugation in D-π-A and D-π-Si-π-A dyads |
| Authors |
Yang-Jin Cho, So-Yoen Kim, Minji Cho, Won-Sik Han1, Sang Ook Kang, Ho-Jin Son*
Department of Advanced Materials Chemistry, Korea University, Korea
1Department of Chemistry, Seoul Women's University, Korea
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| Abstract |
In order to elucidate the influence of π-conjugation on photoinduced electron transfer (PET) and intramolecular charge transfer processes, donor-π-acceptor dyads (D-π-A (1) and D-π-Si-π-A (2)), were newly synthesized. 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 (Δμ=45.6 D) 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: the D+•-π-Si-π-A-• was generated by PET process in the excited state. Each radical species was verified by an fs-TA investigation. We conclude that the disconnection of π-conjugation between the donor and acceptor causes a unit-electron transfer rather than a partial charge transfer. In this case, the linker cannot contribute as a part of the chromophore. In an NLO (nonlinear optical) process such as two-photon absorption, the perturbation between the donor and acceptor demands the π-conjugation of the linker. |
| E-mail |
choyangjin@korea.ac.kr |
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120th General Meeting of the KCS