MORPHOLOGY OF (KC60)(N) POLYMERIC FIBERS

The fibers produced by co-evaporation of C-60 and potassium, and subse quent treatment in toluene, have been investigated by electron microsc opy and optical spectroscopy. The electron diffraction pattern can be indexed in terms of the known orthorhombic (KC60)(n) structure. The fr equencies of the vibrational modes indicate charge transfer between K and C-60, Similar to bulk samples; no anisotropy of optical properties has been observed. The detailed analysis of the electron diffraction and micrographs reveal that, contrary to expectations, the direction o f polymerization does not coincide with the direction of the long axis of the fibers. Furthermore, the structure is twinned, explaining the absence of optical anisotropy.