Electronic and Electric Properties of Peanut-Shaped C_60 Polymers with a Negative Gauss Curvature
When a C60 film was irradiated with an electron-beam with an incident energy of 3 kV and with an current intensity of 0.5 mA under a ultrahigh vacuum condition, a peanut-shaped C60 polymer with a negative Gauss curvature was formed and exhibits a metallic I-V characteristics in air at room temperature. In the present paper, we review the electronic and electric properties of a peanut-shaped C60 polymer using in situ photoelectron spectroscopy and in situ four-probe measurements, together with density-functional calculations of some peanut-shaped C60 polymer model structures, and describe the π-electron conjugated systems from a standpoint of topology.