Numerical simulation evidence of spectrum rearrangement in impure graphene

By means of numerical simulation we confirm that in graphene with point defects a quasigap opens in the vicinity of the resonance state with increasing impurity concentration. We prove that states inside this quasigap cannot longer be described by a wavevector and are strongly localized. We visualize states corresponding to the density of states maxima within the quasigap and show that they are yielded by impurity pair clusters.