Raman scattering of iodine intercalated C60 crystals

Raman scattering spectra of C60 crystals intercalated with iodine have been measured at various temperatures. Three phonon bands related to molecular iodine are observed below 200 cm−1. The observation of these Raman bands suggests that there are different iodine molecular species and that the iodine molecules are deformed. The variations in frequency and intensity with temperature are quite different for the three bands. The anomalous temperature dependence might be related to the rearrangement of iodine molecules in the crystals. No significant frequency shift attributable to charge transfer is found in the intramolecular model of C60.