The well-known homoleptic iridium (III) complex Ir(ppz)3 which is only emissive in solution at low temperature has been investigated as dopant in a p − i stacked OLED architecture. Interestingly, while using this phosphor as a single emitter, awhite OLED was obtained. Emission colour was determined as being concentration and thickness-dependent.
 C. W. Tang and S. A. Van Slyke, Organic electroluminescent
diodes, Appl. Phys. Lett. 51, 1987, 913.
 J. Kalinowski, M. Cocchi, D. Virgili, V. Fattori and J. A. Gareth
Willams, Mixing of Excimer and Exciplex Emission: A New Way
to Improve White Light Emitting Organic Electrophosphorescent
Diodes, Adv. Mater. 19, 2007, 4000.
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