The eight classes of positive-curvature graphitic nanocones.

The eight different classes of single-wall positive-curvature graphitic nanocones are emphasized, characterized, and illustrated. Local transformations among different possible apex-region structures within a common class are investigated, it being noted that there is no short sequence of such transformations which convert from any one of these eight classes to another. Attention is directed to class identification and to nanocone codes, especially for "buckycones" comprised solely from pentagonal and hexagonal rings.