Raman spectra at different temperatures are reported for K3Ba3C60. A systematic change of the Raman spectra with temperature is observed. The development of the linewidth and intensity for all modes with decreasing temperature is in sharp contrast to the case for pure C60. For the two lowest-frequency Hg modes, the appearance of the low-frequency components and an increase in their intensity are observed as temperature decreases. This could be related to an internal strain between the doped part of the crystal and the undoped part of the crystal, and the Jahn-Teller effect. An anomalously large upshift of 9 cm-1 between 20 K and room temperature for the pinch Ag (2) mode suggests the existence of hybridization between the CM molecules and the intercalants. The doublet of Ag(l) at low temperature could arise from the splitting of the crystal field.
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