PROPERTIES OF C-60 POLYMERIZED UNDER HIGH-PRESSURE AND TEMPERATURE

We discuss the Raman, infrared, photoluminescence (PL), x-ray diffract ion (XRD) and laser desorption mass spectroscopic (LDMS) studies of pr essure synthesized C-60 polymers. Pure and mixed phase polymeric sampl es were synthesized by simultaneously subjecting microcrystalline C-60 powder or pellets to various pressures (1 GPa < P < 4.8 GPa) and temp eratures (250 degrees C < T < 600 degrees C). The optical spectra of t he orthorhombic, tetragonal, and rhombohedral C-60 polymer phases are observed to be quite distinct and rich. These spectra exhibit numerous lines and an overall downshift in frequency relative to C-60 is obser ved, consistent with a loss of double bonds from the fullerene cage. T he LDMS spectra of a sample synthesized at 2 GPa under hydrostatic con ditions and 350 degrees C, exhibited a succession of similar to 12 cle ar peaks at mass numbers corresponding to (C-60)N=1,2...12, similar to the LDMS data on the C-60 photopolymer. This is taken as further evid ence for interfullerene bonds in these high-pressure polymers. The XRD pattern of this sample indicates the presence of a strong texture in the sample.