ELECTRONIC PROPERTIES OF A PEANUT-SHAPED C_(60) POLYMER

摘要

In situ valence photoelectron spectroscopy demonstrated that the electronic structure of the EB-irradiated C_(60) film becomes closer to that of graphite as the EB-irradiation time increases, and that the DOS around E_F was eventually greater than for graphite. This indicates that the electronic structure of a C_(60) film was changed from a semiconductor to a semi-metal and/or metal after EB irradiation. It is interesting to note that the DOS at the Fermi edge for the peanut-shaped polymer is very similar to that for one-dimensional metals. Even after the film was exposed to air for 5 days, the electronic structure still remained metallic, which is the origin of the linear Ⅰ-Ⅴ curve of the EB-irradiated C_(60) film obtained in air at room temperature. We explained qualitatively the origin of the electronic properties of the polymer, on the basis of DFT calculations.