| 摘 要： | 1 Results When a C60 film was irradiated with electron-beam (EB) with an incident energy of 3 kV, a peanut-shaped C60 polymer with metallic properties was formed[1], as shown in Fig.1. To elucidate the origin of the metallic properties of the peanut-shaped polymer, we examined the valence photoelectron spectra of the polymer using in situ high-resolution photoelectron spectroscopy and found that the electronic states of the polymer came across the Fermi level (EF)[2]. Interestingly, the spectral shape in the vicinity of the EF remained almost unchanged in a temperature range of 50-350 K, and is very similar to that of quasi one-dimensional materials, such as K0.3MO3, with metallic phase. This predicts that the peanut-shaped polymer has quasi one-dimensional structure with the Peierls transition. If the polymer shows the transition at a given temperature, the spectral shape in the vicinity of the EF should correspondingly be changed around the critical temperature. Indeed, we observed the change of the spectral shape at around 100 K, indicating that some energy gap was formed below the temperature. In addition, the lifetime of the photo-excited carriers increased noticeably at around 60 K.
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