Temperature study of ir spectra of some C/sub 60/ compounds

Summary form only given. Temperature dependence of Fourier-Transform Infrared spectra of C/sub 60/ and its clathrates as well as complexes has been investigated in the temperature range from 100 K to a temperature of material decomposition. The compounds of the formulae: C/sub 60/ S/sub 16/.0.5C/sub 6/H/sub 5/Cl, C/sub 60/.0.5C/sub 6/H/sub 5/Cl, (C/sub 60/)/sub 6/S/sub 80/.C/sub 2/HCl/sub 3/ and (BFDT-TTF) /sub 2/ C/sub 60/ were chosen for the spectral study. The investigation of the full set of infrared-active bands was performed with the purpose of clarifying changes in molecular structure, packing structure, and molecular mobility occurring in the phase transitions of C/sub 60/ derived compounds. The peak frequency, intensity and linewidth of the absorption bands assigned to C/sub 60/ in the compounds under investigation have been found to change in the phase transition temperature region. We compare our IR spectra for C/sub 60/ clathrates and complexes with those obtained for pure C/sub 60/.