RAMAN-SPECTRA OF SINGLE-CRYSTAL C-60

We have analysed the Raman spectra of C60 single crystals between room temperature and 10 K and studied the temperature-induced phase transition in this material. The spectra show crystal field splitting of the internal Raman modes but no evidence for a line shift near the phase transition. The photo-induced transformation of the crystals and its implication on the interpretation of the Raman spectra is discussed. In the low temperature phase we observed two lines at 30 cm-1 and 41 cm-1 which we assign to the librational modes of the crystal.