Imran, Muhammad Sukhanov, Andrey A. Wang, Zhijia Karatay, Ahmet Zhao, Jianzhang Mahmood, Zafar Elmali, Ayhan Voronkova, Violeta K. Hayvali, Mustafa Heng Xing, Yong Weber, Stefan Electronic Coupling and Spin–Orbit Charge-Transfer Intersystem Crossing in Phenothiazine–Perylene Compact Electron Donor/Acceptor Dyads We prepared perylene (Pery)-phenothiazine (PTZ) compact donor/acceptor dyads with connection at either N- or 2-C positions of the PTZ moiety to attain molecular conformation restriction and to study the relationship between mutual chromophore orientation and spin–orbit charge-transfer intersystem crossing (SOCT-ISC) efficiency. In <b>Pery-N-PTZ</b>, the linkage is at the N-position of the PTZ moiety, and the molecule adopts an orthogonal geometry (φ = 91.5°), whereas in <b>Pery-C-PTZ</b>, the connection is at the 2-C position, resulting in a more planar geometry (φ = 60.6°). A diphenylamino derivative (<b>Pery-DPA</b>) was also prepared in which a N atom is fully π-conjugated with the perylene moiety. Highly solvent polarity-dependent singlet oxygen production was observed for the dyads (Φ<sub>Δ</sub> = 3–60%), which is an indication of the SOCT-ISC mechanism. The potential energy curve of the torsion about the C–N/C–C linker indicated different energy landscapes for the dyads; interestingly, we found that nonorthogonal geometry also induces efficient SOCT-ISC, which is different from previous studies. The ultrafast charge separation process (<100 fs) and the ISC rate (0.27 ps) were observed by femtosecond transient absorption spectroscopy. Time-resolved electron paramagnetic resonance spectroscopy further confirmed the SOCT-ISC mechanism. With perylenebisimide as the triplet acceptor and the dyads as the triplet photosensitizer, the triplet–triplet annihilation-induced delayed fluorescence was observed, with the luminescence lifetime up to 71 μs. PTZ moiety;perylene;2- C position;triplet;dyad;spectroscopy;polarity-dependent singlet oxygen production;2- C positions;SOCT-ISC mechanism 2019-03-01
    https://acs.figshare.com/articles/dataset/Electronic_Coupling_and_Spin_Orbit_Charge-Transfer_Intersystem_Crossing_in_Phenothiazine_Perylene_Compact_Electron_Donor_Acceptor_Dyads/7857698
10.1021/acs.jpcc.8b12040.s002