Park Jumi, Sung Jooyoung, Kim Dongho
Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom.
J Phys Chem Lett. 2021 Mar 11;12(9):2226-2231. doi: 10.1021/acs.jpclett.0c03637. Epub 2021 Feb 26.
In this study, we decipher the charge transfer (CT) processes in donor-pyrene-acceptor () molecules via various time-resolved spectroscopic measurements. It has been challenging to unravel the ultrafast CT dynamics in molecules because they exhibit an initial CT emission in the same spectral range as the locally excited (LE) emission. However, we finally observed the CT rate of ∼200 fs in molecules from the time-resolved fluorescence anisotropy decay profiles. Our measurements allow us to suggest that the LE and CT states of systems have isoenergetic potential surfaces and that the introduction of the acceptor to the pyrene moiety gives rise to strong electronic coupling between the LE and CT states. Therefore, we determined that this solvent-independent ultrafast CT occurs through the adiabatic potential energy surface and that the CT characteristics are enhanced in compared to the donor-pyrene-donor system.
