ELASTIC AND DISSIPATIVE PROPERTIES OF C-60 FULLERITE

The attenuation and sound wave velocity of compacted pure C-60 fulleri te were measured in the temperature range of 100 to 300 at the frequen cy of approximate to 5 MHz. Two internal friction peaks were observed. It is concluded that the internal friction peak at 250 K is linked to structural phase transition and the peak at 215 K is due to the relax ation process of reorientation of C-60 molecules. The magnitudes of th e elastic moduli of C-60 fullerite have been estimated. The results ob tained are compared with the theoretical estimations of elastic moduli and experimental data of other authors.