INELASTIC NEUTRON-SCATTERING INVESTIGATION OF QUENCHED CSC60 PHASES

We present an inelastic neutron scattering investigation of the low-fr equency vibrational dynamics of liquid nitrogen-quenched CsC60. The lo w-frequency vibrational signatures of the different phases are discuss ed on the basis of the sequence of phases transitions stated by Kosaka et al. The librational modes of C-60(-) monomer and (C-60)(2)(2-) dim er are observed below 150 K (monomer ordered phase) and around 210 K ( dimer phase) respectively. Above 240 K the appearance of a quasielasti c component agrees with the existence of an orientationally disordered phase. (C) 1998 Elsevier Science Ltd. All rights reserved.