POLYMERIC FULLERENES

Structures, preparation, and physical properties of intrinsic polymeri c fullerenes are reviewed. Three routes to the polymeric state are con sidered: polymerization by light, pressure, and charge transfer. For a ll three processes different types of polymers are known. Polymerizati on by charge transfer is discussed for AC(60), A = K, Rb, Cs. The syst ems for Rb and Cs are quasi-1D metallic at room temperature. KC60 is e ither 3D metallic or phase separates into K3C60 and C-60. Below 50 K R bC60 and CsC60 are insulators due to a spin density wave transition. T he electron-phonon coupling for the molecular modes is unexpected low in the metallic state which is probably the reason for the lack of sup erconductivity in these systems.