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The vacancies are demonstrated to be capable to dramatically alter the graphenes electronic,thermal,and mechanical properties,1-2 and thus adjust the performance of graphene in various applications.With recent development in electron microscopy,great progresses have been achieved in imaging the atomic configuration of a structural defect and exploring their real-time dynamics in situ.3-6 However,the mechanism of the reconstructions of the multiple vacancies(MVs)under EI still remains unkown.In this report,Ill show our recent progress in exploring the evolutions of MVs under EI by long time nonequilibrium molecular dynamics(NEMD)simulations with the classical many-body Brenner potential 8 and first principle calculations.The results present that these MVs tend to form haeckelites,which are characterized by the rotated-hexagon domains isolated by the loops of pentagon-heptagon(57)pairs.It is found that the size of the haeckelite structures increases linearly as a function of the defect fold,n.The relationship can be simply interpreted as a consequence of compensating the losing area induced by atomic removal.Based on this mechanism,the experimentally observed amorphous graphene formation was properly explained.