| abstract |
An organic light emitting device is provided. The device has an anode, a cathode, and a light emitting layer disposed between the anode and the cathode. The emissive layer may comprise a molecule of formula I in which the alkyl substituent at the R ′ 5 position increases the efficiency and stability of use of the organic light emitting device. Additionally or alternatively, the emissive layer can include a metal-ligand complex where the ligand is an aryl or alkyl-substituted phenylpyridine ligand. |