External Magnetic Field Driven, Ambidextrous Circularly Polarized Electroluminescence from Organic Light Emitting Diodes Containing Racemic Cyclometalated Iridium(III) Complexes

This work reports the development of external magnetic field (EMF) driven, ambidextrous, circularly polarized electroluminescence (CPEL) devices, by embedding racemic mixtures of phosphorescent organoiridium(III) emitters in the active emitting layer. Homoleptic tris-cyclometalated Ir(III)(ppy)(3) and heteroleptic bis-cyclometalated Ir(III)(ppy)(2)(acac) (ppy = 2-phenylpyridinate, acac = acetylacetonate) were used as the representative organoiridium(III) compounds. Chiroptical inversion of CPEL was influenced by the ligand environment in the Ir(III) complexes (homoleptic or heteroleptic), as well as the Faraday geometry.