The magnetism induced by D3-symmetry tetra-vacancy defects in graphene was investigated using first principles calculations. It was found that the D3-symmetry tetra-vacancy defects cause remarkable lattice distortion, which significantly alters the electronic structures and magnetic properties of graphene. Moreover, the Lieb’s theorem cannot be used because the bipartite symmetry was broken locally by lattice relaxation. If the dangling bonds around vacancies were passivated by the sp2 hydrogen saturation, the lattice distortion was suppressed. Both the Lieb’s theorem and tight-binding method can thus be used.

Magnetism Induced by D3-Symmetry Tetra-Vacancy Defects in Graphene. Z.Bao, J.Shi, M.Yang, S.Zhang, M.Zhang: Chemical Physics Letters, 2011, 510[4–6], 246–51