Properties of C 60 polymerized under high pressure and temperature

polymers. Pure and mixed phase polymeric samples were synthesized by simultaneously subjecting microcrystalline C60 powder or pellets to various pressures ( \valunit{1}{GPa} < P < \valunit{4.8}{GPa} ) and temperatures ( \valunit{250}{\celsius} < T < \valunit{600}{\celsius} ). The optical spectra of the orthorhombic, tetragonal, and rhombohedral C60 polymer phases are observed to be quite distinct and rich. These spectra exhibit numerous lines and an overall downshift in frequency relative to C60 is observed, consistent with a loss of double bonds from the fullerene cage. The LDMS spectra of a sample synthesized at \valunit{2}{GPa} under hydrostatic conditions and \valunit{350}{\celsius} , exhibited a succession of \sim 12 clear peaks at mass numbers corresponding to (\chem{C_{60}})_{{N} = 1, 2\ldots 12} , similar to the LDMS data on the C60 photopolymer. This is taken as further evidence for interfullerene bonds in these high-pressure polymers. The XRD pattern of this sample indicates the presence of a strong texture in the sample.