Electron-transporting properties of a series of trivalent rare earth ion (RE3+) complexes in multilayer organic electroluminescent (GEL) devices have been studied, The emitting layer (EML) in the devices consists of trivalent europium (Eu3+) complexes dispersed into PVK [poly(N-vinylcarbazole)] film. (C) 1997 Elsevier Science S.A.