Structural (XRD and HRTEM) investigations of fullerite C60 and C70 samples

Since the carbon states on the basis of C60 and C70 exhibit very interesting physical properties such as hardness exceeding diamond, we focused our investigations on the comparison of structures of the C60 and C70 hard phases synthesized at high pressure and high temperatures. X-ray diffraction (XRD) and high-resolution transmission electron microscope (HRTEM) investigations have revealed that two states (amorphous and nanocrystalline) co-exist in samples of both kinds of fullerites. The difference between the diffraction patterns of C60 and C70 has been ascribed mainly to the grade of disorder. The XRD and HRTEM results have been correlated with the transport properties (electrical and thermal conductivity) of the samples.