Raman study of C60/polymethyl methacylate film

C60/polymethyl methacylate (PMMA) composite films were prepared by the sol–gel method. Fourier transform infrared spectra of the as-prepared samples showed that C60 is incorporated into PMMA and its structure is retained in the fabrication process. A substantial red shift of the high frequency, the Ag(2) pentagonal pinch mode, was observed from Raman scattering measurement at room temperature. To our knowledge, this is the first time to find such phenomenon correlated with the charge transfer between the two phases in C60/PMMA films. Moreover, the phonon softening was compared with a theoretical calculation performed in graphite intercalation compounds. The charge transfer effect was also evidenced with ultraviolet–visible observations.