morphologies correspond to those drawn in Figs. \[Vac4\]b, c, and d with non-zero magnetic moments.

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The discussion above show that SVs in a graphene are rather mobile defects, which may migrate and coalesce with other single vacancy forming a DV or with other polyvacancies even at temperatures slight higher than that of a room temperature. DVs are immobile defects at room temperature. Nevertheless they can migrate either at higher temperatures or by means of transformation to other DV modifications. The mobile defects are reincorporated into the crystal structure at dislocations, grain boundaries and other defect sinks or at the crystal external surfaces.

Summarizing all these calculation results, one can conclude that (i) among of the vacancy clusters with even vacancies there is at least one cluster where the dangling bond is absent. The magnetic moment of such vacancy cluster is zero, and the formation energy of such cluster is less than those of all other clusters with the equal number of the vacancies; (ii) among of the clusters with odd vacancies there is at least one configuration which contains only one dangling bond. The formation energy of such cluster is minimal among of all clusters with equal 