  We present an ab initio study on the structural and electronic distortions of
modified graphene by creation of vacancies, inclusion of boron atoms, and the
coexistence of both, by means of thermodynamics and band structure
calculations. In the case of coexistence of boron atoms and vacancy, the
modified graphene presents spin polarization only when B atoms locate far from
vacancy. Thus, when a boron atom fills single- and di-vacancies, it suppresses
the spin polarization of the charge density. In particular when B atoms fill a
di-vacancy a new type of rearrangement occurs, where a stable BC4 unit is
formed inducing important out of plane distortions to graphene. All these
findings suggest that new chemical modifications to graphene and new type of
vacancies can be used for interesting applications such as sensor and chemical
labeling.
