The role of the interface in the electronic structure of adsorbed metal(II) (Co, Ni, Cu) phthalocyanines

We compare the electronic structures of metal(II) (Co, Ni, Cu) phthalocyanines adsorbed on conducting and insulating substrates: Au(111) and the organic ferroelectric polyvinylidene fluoride (PVDF). The different 3d orbital contributions to the metal phthalocyanines result in different substrate interactions, and different molecular orbital offsets. When adsorbed on the ferroelectric PVDF surface, the photoemission and inverse photoemission spectra suggest that cobalt phthalocyanine (CoPc) bonds more strongly to both Au(111) and PVDF, resulting in a preferential planar configuration on the PVDF surface, not observed with nickel phthalocyanine (NiPc) and copper phthalocyanine (CuPc).