Metal-Free OLED Triplet Emitters by Side-Stepping Kasha’s Rule (pages 13449–13452)
Dr. Debangshu Chaudhuri, Dr. Eva Sigmund, Annemarie Meyer, Lisa Röck, Philippe Klemm, Sebastian Lautenschlager, Agnes Schmid, Shane R. Yost, Prof. Dr. Troy Van Voorhis, Dr. Sebastian Bange, Prof. Dr. Sigurd Höger and Prof. Dr. John M. Lupton
Article first published online: 7 NOV 2013 | DOI: 10.1002/anie.201307601
Keeping it light: Most organic fluorophores do not show useful emission from the triplet excited state. A new class of materials is presented for organic light-emitting diodes that exhibit phosphorescence under electrical excitation, even at room temperature, without employing the heavy-atom effect. Blocking of internal conversion is so effective that emission from higher-lying triplet states, above the singlet, can be observed at low temperature.