CONDUCTING PHASE OF RAPIDLY COOLED AC(60) (A=CS AND RB)

A three-dimensional (3D) conducting phase is found upon rapid cooling below 150 K for CsC60 and below 125 K for RbC60. Electron-spin resonance, differential thermal analysis, differential scanning calorimetry, and x-ray-diffraction results suggest that the 3D conducting phase is an orientationally ordered (possibly simple-cubic) phase. We propose a complete relation for the various states for AC60. The rapidly cooled AC60 shows a number of phase changes as the temperature increases from 4 to 473 K. © 1995 The American Physical Society.