Characterizing reactions to fabricate thin films of charge transfer complexes by synchrotron photoelectron spectroscopy: A case study of DCNQI-Cu

Ultraviolet photoelectron spectroscopy with various photon energies using synchrotron radiation was used to characterize chemical reactions associated with thin film growth of organic charge transfer complex (DMe-DCNQI)2Cu. Other molecular systems H2Pc, CuPc and C60 were also studied to clarify the origin of the systematic relation between the spectra and the incident photon energy. Characteristic photon energy dependence of the photo-ionization cross section of molecular orbitals is useful to analyze the intermolecular reactions.