energy $\sim 11.27~eV$ and the magnetic moment $\sim 2.02~\mu_B$. The tetra-vacancy structure [*55-12*]{} of two pentagon and one dodagon defects, presented in Fig. \[Vac4\]d, is produced by removing four nearest-neighboring atoms in a hexagon. The same relaxed supercell with [*55-12*]{} defect is obtained by removing two nearest-neighboring atoms in one side and two similar atoms in other side of the hexagon so that these pairs are not connected each other. The formation energy and the magnetic moment of this type of defects are $13.33~eV$ and $1.99~\mu_B$ correspondingly. A small band gap is opened around the Fermi level in these configurations, the band structures of which are presented in Fig. \[Vac4\]b, c, and d, yielding quasi-localized states. Note that there is an imbalance of the vacancies between the sublattices A and B in the tetra-vacancy depicted in Fig. \[Vac4\]a, since 3 vacancies belong to one sublattice and only one vacancy belongs to other sublattice. Nevertheless, the number of vacancies located in A and B sublattices are equal each other in other three tetra-vacancy configurations of Figs. \[Vac4\]b, c, and d. Note that tri- and tetra-vacancy have been studied [@tlhb14] by coalescing a mono-vacancy to di- and tri-vacancy, correspondingly. Therefore, the obtained 