A MAIN DIMER OF FULLERENES - C-118

A photopolymerization of C-60 molecules occurs in the irradiation of o xygen-free C-60 film with visible or ultraviolet light. Results from m ass spectroscopy indicate that C-118 is the principal dimer among the dimers around C-120. Three most possible isomers of C-118 are presente d and studied. Geometries are optimized with tight-binding method and two techniques. Vibrational modes are also obtained. Their stretching frequencies are from 106 cm(-1) to 133 cm(-1), which are consistent wi th the experimental value 116 cm(-1).