Isomeric Formation of 5|8|5 Defects in Graphenic Systems

An innovative mechanism leading to the formation of 5|8|5 defects in graphenic systems is presented. These twofold-symmetrical defects, made by an octagon and two opposing pentagonal rings, emerge from sequences of Stone-Wales rotations, the so-called Stone-Wales waves recently introduced to induce isomeric modifications of the graphene plane, excluding the divacancy mechanism normally used in literature. This topological generation of 5|8|5 defects preserves the number of atoms and bonds of the system and may help researchers in modeling defective graphene, a material with unique magnetic and electronic properties. Isomeric configurations are ranked by means of the topological potentials.