The complex nature of phthalocyanine/gold interfaces

We compare the electronic properties of the interface between Au(1 0 0) and cobalt phthalocyanine (CoPc), fluorinated F16CoPc as well as CuPc using X-ray photoemission spectroscopy and valence band ultra-violet photoemission spectroscopy. Our results show that in addition to the formation of an interface dipole at the interfaces of CoPc and F16CoPc to gold, there is a local charge transfer to the central Co ion, which as a result is reduced to Co(I).