有机发光二级管(OLEDs)的不同折光指数多层器件结构特点，造成大部分电致发光不能有效利用,成为其发展的瓶颈之一。提高器件光耦合输出效率的传统物理方法对器件大规模生产与实际应用造成严重困扰。在对目前提高有机电致发光器件光耦合输出效率所面临的困境和亟待解决的难点问题进行系统梳理的基础上，本项目首次利用操控磷光分子内电子跃迁过程，实现分子最长维度与其跃迁偶极方向统一的科研思想，深层优化磷光分子跃迁偶极水平取向度，设计合成新型非对称2-苯基吡啶类(ppy)Ir(III)配合物磷光分子，达到提高有机电致发光器件光耦合输出效率的目的。在此基础之上，深入探讨此类新型非对称磷光分子跃迁偶极水平取向行为与其化学结构之间的构-效关系规律。本项目研究不仅为新型高效磷光材料的设计合成提供新的理论依据，而且对高效有机电致发光器件的研制也具有重要的应用价值。

The structure features of multi-layer with different refraction index of organic light-emitting diodes (OLEDs) have left majority fraction of electroluminescent unharness, representing one of the bottleneck problems in the developing of OLEDs. The traditional physical light outcoupling strategies typically set serious restrictions for the large-scale production and practical application of the devices. Based on the systematic analysis of the technical bottlenecks and obstacles for the light outcoupling strategies presently employed in OLEDs, the research idea of fulfilling the unity of directions between the longest dimension of the phosphorescent molecules and their transition dipole through manipulating the molecular electron transition process has been employed for the first time to deeply optimize their horizon orientation behavior of the transition dipole. Based on this idea, novel unsymmetric 2-phenylpyridine (ppy) type phosphorescent molecules have been designed and prepared with the aim to improve the light outcoupling efficiency of OLEDs. Furthermore, the relationship between the chemical structures of the concerned phosphorescent molecules and their horizon orientation behaviors of the transition dipole will be explored in depth. The research not only can provide theory basis for the design and synthesis of novel high performance phosphorescent emitters, but also has important application value for the design and fabrication of highly efficient electroluminescent devices.