title: Photoinduced charge-transfer dynamics of sequentially aligned donor-acceptor systems in an ionic liquid.
abstract: Photoinduced charge separation processes of linear phenyleneethynylene derivatives (PEN) with different sequences of electron-withdrawing perfluorophenyl groups (A) and electron-donating phenyl groups (D) were investigated in an ionic liquid (IL), BmimTFSI, by picosecond time-resolved fluorescence (TRF) and transient absorption (TA) spectroscopies. Very rapid photoinduced charge separation within 10 ps in AADD was followed by the stabilization of the charge-transfer (CT) state by the solvation, while the excited states in ADAD and ADDA were ascribable to the locally excited (LE) state. Equilibrium between the LE and CT states was established for DAAD with time constants of forward and backward processes much faster than the solvation time. The relative population of the CT state increases with time owing to the dynamic stabilization of the CT state by the solvation. The elementary charge separation process, the increase in the CT population, and their relation to the solvation time were discussed.
authors: Division of Frontier Materials Science, Graduate School of Engineering Science and Center for Quantum Science and Technology under Extreme Conditions, Osaka University, Toyonaka, Osaka 560-8531, Japan. nagasawa@chem.es.osaka-u.ac.jp miyasaka@chem.es.osaka-u.ac.jp.
authors: Masayasu
authors: M
authors: Muramatsu
authors: Tetsuro
authors: T
authors: Katayama
authors: Syoji
authors: S
authors: Ito
authors: Yutaka
authors: Y
authors: Nagasawa
authors: Daisuke
authors: D
authors: Matsuo
authors: Yoshinori
authors: Y
authors: Suzuma
authors: Lifen
authors: L
authors: Peng
authors: Akihiro
authors: A
authors: Orita
authors: Junzo
authors: J
authors: Otera
authors: Hiroshi
authors: H
authors: Miyasaka