Amorphization of Rb₆C₆₀ and Cs₆C₆₀ under high-temperature and high-pressure conditions

Abstract

X-ray diffraction measurements have been performed on Rb₆C₆₀ and Cs₆C₆₀ compounds at a constant pressure around 5 GPa as a function of temperature. The data show the occurrence of an irreversible transition starting at 900 K for Cs₆C₆₀ and 1300 K for Rb₆C₆₀ leading to a progressive amorphization of both compounds. Raman data collected at ambient conditions on the recovered samples show that such transition is accompanied in both cases by the loss of the molecular character of the system.

Keywords:

• fullerides
• high pressure
• high temperature
• X-ray diffraction
• Raman spectroscopy