Structures of carbon cluster ions from 3 to 60 atoms: Linears to rings to fullerenes

A new method for identifying and characterizing cluster ion isomers is presented. Results indicate that most carbon clusters have more than one stable form, with 29≤n≤45 indicating three or four different structures. Fullerenes first appear at C+30 and begin to dominate above C+45. From small to large the isomeric progression is from linear to rings to fullerenes.