Highly Efficient Organic Light‐Emitting Diodes with Phosphorescent Emitters Having High Quantum Yield and Horizontal Orientation of Transition Dipole Moments

Ancillary ligands in heteroleptic iridium complexes significantly influence the orientation of the transition dipole moments. Ir(ppy)3, a homoleptic iridium complex, exhibits isotropic dipole orientation, whereas the heteroleptic Ir complexes of Ir(ppy)2tmd show a highly preferred dipole orientation (78%) in the horizontal direction. In addition, we demonstrate an unprecedented highly efficient green OLED exhibiting an EQE of 32.3% and a power efficiency of 142.5 lm/W by using an emitter with high quantum yield and horizontally oriented dipoles. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.