CARBON-FLUORINE BONDINGS OF FLUORINATED FULLERENE AND GRAPHITE

Carbon-fluorine bondings of fluorinated fullerenes and fluorine-graphite intercalation compound CxF were investigated in detail on the basis of XPS data and the potential model using the charge distribution calculated by semiempirical method. It has been confirmed by the present study that two peaks in the CI, spectra observed for fluorinated fullerenes are assigned to carbon atoms bonded to fluorine atoms and those unbound to fluorine atoms, and the small difference in charges and Madelung potentials of fluorine atoms in different circumstances well explains the single peak in F-1s spectra of fluorinated fullerenes. In the calculated structures of 1,3-C60F2 and 1,2-C60Fx (x = 2-6) used as the models of CxF, three kinds of carbon-fluorine bondings were observed corresponding to nearly ionic, semicovalent and covalent C-F bondings. The calculated result supports that the bi-intercalation structure of stage 1 CxF consists of nearly ionic and semi-covalent fluorines.