The interaction of aluminum and p-sexiphenyl

Aluminum is widely used as cathode material in organic electroactive device s. In this work the interface formation between the electroluminescent mate rial p-sexiphenyl(6P) and this metal was investigated with photoelectron sp ectroscopy. In strong contrast to the findings for the interaction of polye nes and oligothiophenes with Al, where covalent bonds are formed, we obtain clear evidence for physisorption of Al on 6P. This is supported by quantum chemical calculations, carried out on model systems.