Synergistic Modulation of Excited State Ingredients and Chiroptical Activity for High‐Performance Pure‐Green Circularly Polarized Electroluminescence

AbstractThe integration of chiral elements within a multiple resonance (MR) motif affords a prospective avenue to construct satisfying emitters tailored for state‐of‐the‐art circularly polarized organic light–emitting diodes (CP‐OLEDs). However, the concurrently realizing of both high luminescence efficiency and favorable dissymmetry factors (gPL) still remains a formidable challenge, particularly when aligning with the requirement of high color purity. Herein, a dual‐pronged approach is proposed to reconcile such trade‐offs by directly fusing a secondary chiral donor onto the MR scaffold, thereby facilitating a hybrid short/long‐range charge‐transfer with fine‐tuned compositions. Theoretical calculations unveil the pronounced impact of the chiral donor on meticulously refining the characteristics of excited states, therefore yielding a considerable gPL of 3.3 × 10−3, along with a high fluorescence quantum yield of 0.97, and a rapid reverse intersystem crossing rate of 3.06 × 105 s−1 in one embodiment. Leveraging these merits, electroluminescence devices incorporating them as chiral dopants exhibit exceptional performance, showcasing a peak external quantum efficiency of 36.6% and remarkable Commission Internationale de L'Eclairage coordinates of (0.19, 0.71), which represent one of the most notable achievements among pure‐green CP‐OLEDs.