A 4‐amino‐2,2,6,6‐tetramethyl‐1‐piperidinyloxyl (TEMPO) radical was attached to the bay position of perylene‐3,4 : 9,10‐bis(dicarboximide) (perylenebisimide, PBI) to study the radical‐enhanced intersystem crossing (REISC) and electron spin dynamics of the photo‐induced high‐spin states. The dyads give strong visible light absorption (ϵ=27000 M⁻¹ cm⁻¹at 607 nm). Attaching a TEMPO radical to the PBI unit transforms the otherwise non‐radiative decay of S₁ state (fluorescence quantum yield: Φ_F=2.9 %) of PBI unit to ISC (singlet oxygen quantum yield: Φ_Δ=31.8 %, Φ_F=1.6 %). Moreover, the REISC is more efficient as compared to the heavy atom effect‐induced ISC (Φ_Δ=17.8 % for 1,8‐dibromoPBI). For the dyad, ISC takes 245 ps and triplet state lifetime is 1.5 μs, much shorter than the native PBI (τ_T=126.6 μs). X‐ and Q‐band time‐resolved electron paramagnetic resonance spectroscopy shows that the exchange interaction in the photoexcited radical‐chromophore dyad is larger than the triplet zero‐field splitting (ZFS) and the difference of Zeeman energies of the radical and chromophore. The inversion of electron spin polarization from emissive to absorptive was observed and attributed to the initial completion of the quartet state population and the subsequent depopulation processes induced by the zero‐field splitting.

中文翻译：

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湾取代的Bi双酰亚胺-TEMPO二元化合物的自由基增强的系统内交叉和光激发后的电子自旋极化动力学**

一个4-氨基-2,2,2,6,6-四甲基-1-哌啶基氧基（TEMPO）自由基连接到per 3,4的托架位置：9,10-双（二甲叉酰亚胺）（per二酰亚胺，PBI）进行研究光诱导的高自旋态的自由基增强的系统间穿越（REISC）和电子自旋动力学。二面体提供强的可见光吸收（在607nm处ϵ＝ 27000M ^-1  cm ^-1）。附加TEMPO自由基的PBI单元变换的否则非辐射衰减第_1种状态（荧光量子产率：Φ _˚F = 2.9％）PBI单元对ISC（单线态氧量子产率：Φ _Δ = 31.8％，Φ _˚F= 1.6％）。此外，相比于重原子效应诱导的ISC（该REISC是更有效的Φ _Δ为1,8- dibromoPBI = 17.8％）。对于二分体，ISC花费245个PS和三重态寿命为1.5 μ S，比天然PBI（短得多τ _Ť = 126.6 μs）。X和Q波段时间分辨电子顺磁共振光谱显示，光激发的自由基发色团二元组中的交换相互作用大于三重态零场分裂（ZFS）以及自由基和发色团的塞曼能差。观察到电子自旋极化从发射转变为吸收，这归因于四方态种群的初始完成和随后的零场分裂引起的人口减少过程。