atoms belonging to the same sublattice stabilizes the vacancy extended states. The third dangling bond is left unsaturated and contributes $\approx 1~\mu_B$ in magnitude magnetic moment to the intrinsic magnetization. Removing one-, two- and three-carbon atoms located in the nearest-neighboring sites in the unit cell results in formation of correspondingly [*5-9*]{}, [*5-8-5*]{}, and [*55-10*]{} type defective configurations in the supercell (see, Fig. \[Vac1\]). DOS, the band structure, and the distributions of the deformation potential around the mono-, di-, and tri-vacancy distortions are depicted in Fig. \[Vac1\]. The deformation potential is seen to be significant within the unit cell around the vacancy. Therefore, interaction of vacancies through the distortion potential seems to be like to the dipole interaction and it would be important only for vacancies placed nearest-neighbor each other. The vacancies located far away each other may be considered practically as isolated vacancies. Formation energy of a single vacancy is calculated to be $6.99~eV$ (see, Table \[table2\]). This result is slightly lower than those obtained by other authors $E_f \approx 7.5~eV$ [@eteh03; @mlfn04; @klfn06], nevertheless it is in good consistence with the experimental data of $7.0 \pm 0.5~eV$ [@tm78].

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The spin-polarized electronic band structures of a defective graphene 