Characterization of fullerenes and doped fullerenes
Abstract
The results of a variety of experiments used to characterize fullerenes, metallofullerenes and alkali-metal intercalated C60 are reported. It is shown that differential scanning calorimetry and NMR characterization of the orientational phase transition in C60 provide sensitive means to assess the purity and crystallinity of fullerene samples. The results of a mass-spectrometric investigation of metallofullerene samples produced by co-vaporization of carbon and metals are described. An account is given of some electron paramagnetic resonance results obtained for LaC82 and solid-state NMR results obtained on an alkali-intercalated fullerite, Rb3C60, which show for the first time the presence of magnetically inequivalent carbons in underivatized C60. Together these experiments yield a great deal of information about the phase purity, molecular dynamics and structure of a variety of fullerene materials. © 1993.