Polymeric phases of C60

• We have investigated the "low" pressure region where C60 can be transformed into polymeric chains or clusters. To learn more about the polymerization process we have treated pristine C60 at several different temperatures under hydrostatic pressures in silicone oil. We found that the reaction rate varied with temperature. Above 520 K at 1.0 GPa similar and high polymer fractions were obtained in all samples, but at 497 K the polymer fraction was only 10% after three hours, as indicated by the shift of the intensity of the pentagonal pinch mode in the Raman spectrum. Also, samples treated at the same pressure and temperature but with different thermal pre-history showed different degrees of polymerization. We have also found a correlation between the shift of the pentagonal pinch mode in the Raman spectrum to 1463 /cm and the intermolecular vibrational mode at 97 /cm. We therefore make the conclusion that the shift of the pentagonal pinch mode to 1463 /cm corresponds to the presence of dimers in the sample.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Keyword

Fullerenes

C60

high pressure synthesis

polymerization

polymer chains

dimers

Raman spectroscopy

Raman spectra

Condensed matter physics

Kondenserade materiens fysik

fysik

Physics

Publication and Content Type

ref (subject category)

kon (subject category)