Abstract Novel thermally-activated delayed fluorescence (TADF) host materials were designed for blue electrophosphorescence by combining electron donor acridine derivatives with the electron acceptor phenoxaphosphine (OPO) unit using the density functional theory. We obtained the energies of the first singlet (S1) and first triplet (T1) excited states of these TADF materials by performing density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations on the ground state using a dependence on charge transfer amounts for the optimal Hartree-Fock percentage in the exchange-correlation of the TD-DFT. Using DFT and TD-DFT calculations, the large separation between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) gives a small energy difference (ΔEST) between the S1 and T1 state. These host molecules could retain high triplet energy, and they showed great potential for blue phosphorescent organic light-emitting diodes (OLEDs). We demonstrated that these molecules are promising host materials with a lower barrier for hole and electron injection; these also provide balanced charge transport for both hole and electron and small ΔEST.

中文翻译：

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用于使用热激活延迟荧光的蓝色 OLED 的基于贵重苯氧膦的双极主体

摘要 利用密度泛函理论，通过将电子供体吖啶衍生物与电子受体苯氧膦 (OPO) 单元相结合，设计了用于蓝色电致磷光的新型热激活延迟荧光 (TADF) 主体材料。我们通过对基态进行密度泛函理论 (DFT) 和瞬态 DFT (TD-DFT) 计算，获得了这些 TADF 材料的第一个单重态 (S1) 和第一个三重态 (T1) 激发态的能量。 TD-DFT 的交换相关性中最佳 Hartree-Fock 百分比的电荷转移量。使用 DFT 和 TD-DFT 计算，最高占据分子轨道 (HOMO) 和最低未占据分子轨道 (LUMO) 之间的大分离给出了 S1 和 T1 状态之间的小能量差 (ΔEST)。这些主体分子可以保留高三线态能量，它们在蓝色磷光有机发光二极管 (OLED) 方面显示出巨大的潜力。我们证明了这些分子是有前途的主体材料，具有较低的空穴和电子注入势垒；这些还为空穴和电子以及小 ΔEST 提供了平衡的电荷传输。