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In this paper, we present a systematic theoretical investigation of the phthalocyanine based dimer MnPcδ+/F16CoPcδ- within density functional theory framework. For all considered stacking geometries, a charge transfer from MnPc to F16CoPc is observed which is therefore identified as an intrinsic property of the molecular pair. In addition, a ferromagnetic coupling of the molecular magnetic moments within the dimer is always observed due to 90∘ superexchange and direct-exchange contributions. The comparison of the calculated absorption spectra of the different stacking arrangements to the experimentally recorded electron energy-loss spectrum strongly indicates the β stacking to be preferred over all others. Only for this geometry an experimentally observed excitation around 0.6 eV is reproduced by the calculation. [ABSTRACT FROM AUTHOR]

We have prepared mixed phthalocyanine films out of MnPc and F16CoPc, which were characterized by means of photoemission spectroscopy and electron energy-loss spectroscopy. Our data reveal the formation of MnPc/F16CoPc charge transfer dimers in analogy to the related heterojunction. The electronic excitation spectrum of these blends is characterized by a new low energy excitation at 0.6 eV. Density functional theory calculations show that the new signal is caused by a strong absorption between the states of the interface induced two level system. [ABSTRACT FROM AUTHOR]

Using photoelectron spectroscopy we demonstrate charge transfer at an interface between two well-known transition metal phthalocyanines, MnPc and F16CoPc, resulting in charged MnPcδ+ and F16CoPcδ- species. Moreover, the transferred charge is substantially confined to the two transition metal centers. Density functional theory calculations reveal that a hybrid state is formed between the two types of phthalocyanines, which causes this charge transfer. For the hybrid state the Mn 3dxz interacts with the Co 3dz2 orbital leading to a two-level system. As only the lower of the two hybrid states is occupied, the charge is directly transferred to the Co 3dz2 orbital. [ABSTRACT FROM AUTHOR]