Polyyne wire

FIGURE 1.8 TheFullereneCgo, a Fullerene Compound, a Carbon Nanotube, Graphene, a Carbon Peapod, and a Polyyne "Wire" Connecting Platinum Atoms. 

The small clusters of carbon, with a few added elements, can resemble any of these forms. Pure carbon clusters, up to ten atoms or so, are either linear or cyclic, most strongly resembling the graphite or polyyne forms. Larger cluster sizes, or impurity atoms, stabilize the diamond form. The graphite and polyyne forms have in common a conjugated tt electron system, so these small carbon clusters and their relatives may be cultivated into wires for nanometer-scale electronics. 

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