| abstract |
A linght emitting device comprising: an anode; a cathode; a light emissive layer located between the anode and the cathode, said light emissive layer comprising a charged metal complex for emitting light and a counterion or counterions with sufficient charge to balance the change on the charged metal complex; characterised in that the counterion or counterions are substantially immobile so (that light output from the device is immediate, provided that the combined charged metal complex and counterion do not have General Formula: (I) or (II): where C-N is a cyclometallated ligand. |