Pressure-induced irreversible amorphization of C-70 fullerene

We report Raman scattering study of Cio fullerene polycrystals undertaken a t high static pressures up to 51 GPa using a diamond-anvil cell. Above 12 G Pa, a majority of the intramolecular vibrational modes lost their intensiti es and only one broad peak initially centered at 1567 cm(-1) was found to p ersist, indicating an occurrence of amorphization. Analysis of the line wid th of the 1567 cm(-1) peak showed the amorphization to be completed by abou t 18 cpa. The amorphous phase was irreversibly retained to the ambient pres sure after pressures higher than 35 GPa were applied. (C) 2000 Elsevier Sci ence Ltd. All rights reserved.