Abstract Different molecular design strategies have been performed to study purely organic materials with room-temperature phosphorescence (RTP) by suppressing nonradiative deactivation and facilitating intersystem crossing. In this work, a synthetic strategy based on CPM ((9H-carbazol-9-yl)(phenyl)methanone) has been performed to achieve long lived RTP by immobilizing the torsion of benzophenone moiety and forming a six-membered heterocyclic ring containing nitrogen element. This synthesized locked-CPM (8H-indolo[3,2,1-de]phenanthridin-8-one) with higher rigidity has planar configuration both in the singlet state and the triplet state, whose locking configuration effectively inhibits the twist intramolecular charge transfer (TICT) of CPM and significantly reduces the energy gap between the singlet and triplet states to 0.89 ev. This change facilitates intersystem crossing and the generalization of triplet excitons. By fitting the phosphorescence decay curves, we demonstrate that the phosphorescence lifetime of the locked-CPM has increased by nearly forty times compared with that of the CPM, indicating that the presented strategy will bring insight into the developing long lived RTP materials. It is noted that suppress the vibration and torsion of molecular and reduce the energy gap between single-triplet states will favors of long phosphorescence lifetime.

中文翻译：

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(9H-咔唑-9-基)(苯基)甲酮的结构锁定诱导磷光寿命增强：一种有机磷光材料

摘要 不同的分子设计策略通过抑制非辐射失活和促进系统间交叉来研究具有室温磷光 (RTP) 的纯有机材料。在这项工作中，基于 CPM（（9H-咔唑-9-基）（苯基）甲酮）的合成策略通过固定二苯甲酮部分的扭转并形成含氮的六元杂环来实现长寿命的 RTP。元素。这种具有较高刚性的合成锁定CPM（8H-indolo[3,2,1-de]phenanthridin-8-one）在单线态和三线态均具有平面构型，其锁定构型有效地抑制了扭曲分子内电荷转移(TICT) 的 CPM 并显着降低单线态和三线态之间的能隙至 0.89 ev。这种变化促进了系统间交叉和三重态激子的泛化。通过拟合磷光衰减曲线，我们证明与 CPM 相比，锁定 CPM 的磷光寿命增加了近 40 倍，表明所提出的策略将深入了解正在开发的长寿命 RTP 材料。值得注意的是，抑制分子的振动和扭转，减小单三重态之间的能隙有利于长磷光寿命。表明所提出的策略将深入了解开发中的长寿命 RTP 材料。值得注意的是，抑制分子的振动和扭转，减小单三重态之间的能隙有利于长磷光寿命。表明所提出的策略将深入了解开发中的长寿命 RTP 材料。值得注意的是，抑制分子的振动和扭转，减小单三重态之间的能隙有利于长磷光寿命。