ABSTRACT
In this chapter it has been shown that transport measurements, transmission electron microscopy (TEM), electron spin resonance (ESR), and optical meas urements all indicate that the structure and properties of fluorine-GICs are quite different from that of most other known GICs (Table 8). Usually, the charge transfer associated with intercalation increases the metallic character of the intercalation compound as compared to pristine graphite. In contrast, most fluorine-GICs are more resistive than pristine graphite, and beyond a concentra tion C4F, they exhibit a semiconducting dependence of resistivity on temperature [42,99]. Furthermore, the planarity of the carbon planes does not persist after intercalation of fluorine, and TEM micrographs (Fig. 8) show that the carbon planes in fluorine-GICs are buckled [20]. The unique electronic and structural properties of fluorine-GICs are especially striking compared to other halogenGICs, which have a similar chemical structure.
