An atomic force microscopic examination was made of the photo-induced surface reconstruction of C60 single crystals. The (111) and (001) faces of C60 single crystals were illuminated with photons with energies below the band gap (generation of Frenkel-type excitons) or above the band gap. In the case of sub-bandgap illumination, reconstructed surfaces formed on the crystals. The reconstruction was represented by fringes running in the [11¯2] and [0¯10] directions on the (111) and (001) surfaces, respectively. As a result of supra-bandgap illumination, there appeared only cracks - without any fringes - which were oriented in directions characteristic of each face. The results suggested that the photo-induced surface reconstruction of C60 single crystals was induced via the recombination of Frenkel-type excitons.

AFM Observation of Surface Reconstruction of C60 Single Crystals. Y.Kim, L.Jiang, T.Iyoda, J.Li, K.Kitazawa, K.Hashimoto, A.Fujishima: Applied Physics A, 1998, 66[1], S763-6