Herein, we introduce the cyclic 8π‐electron (C8π) molecule N,N′‐diaryl‐dihydrodibenzo[a,c]phenazine (DPAC) as a dual‐functional donor to establish a series of new donor–linker–acceptor (D–L–A) dyads DLA1–DLA5. The excited‐state bent‐to‐planar dynamics of DPAC regulate the energy gap of the donor, while the acceptors A1–A5 are endowed with different energy gaps and HOMO/LUMO levels. As a result, the rate and efficiency of the excited‐state electron transfer vs. energy transfer can be finely harnessed, which is verified via steady‐state spectroscopy and time‐resolved emission measurements. This comprehensive approach demonstrates, for the first time, the manifold of excited‐state properties governed by bifunctional donor‐based D–L–A dyads, including bent‐to‐planar, photoinduced electron transfer (PET) from excited donor to acceptor (oxidative‐PET), fluorescence resonance energy transfer (FRET), bent‐to‐planar followed by electron transfer (PFET), and PET from donor to excited acceptor (reductive‐PET).

中文翻译：

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供体-受体-受体二元组受供体的弯曲到平面运动控制的多种激发态弛豫途径。

在此，我们将环状8π-电子（C8π）分子N，N'-二芳基-二氢二苯并[ a，c ]吩嗪（DPAC）用作双功能供体，以建立一系列新的供体-连接子-受体（D- L–A）二元组DLA1 – DLA5。DPAC的激发态从弯曲到平面的动力学调节了施主的能隙，而受主A1 - A5具有不同的能隙和HOMO / LUMO水平。结果，可以很好地利用激发态电子转移与能量转移的速率和效率，这可以通过稳态光谱学和时间分辨发射测量得到验证。这种全面的方法首次证明了受双功能基于供体的D–L–A二元体系所控制的激发态特性的多种多样，包括从激发供体到受体（氧化）的弯曲至平面光诱导电子转移（PET） -PET），荧光共振能量转移（FRET），弯曲至平面然后电子转移（PFET）以及从供体到受激受体的PET（还原性PET）。