Substitutional impurity in the graphene quantum dots

The process of formation of the localized defect states due to substitutional impurity in sp(2)-boncled graphene quantum dot is considered using a simple tight-binding-type calculation. We took into account the interaction of the quantum clot atoms surrounding the substitutional impurity from the second row of elements. To saturate the external dangling sp(2) orbitals of the carbon additionally 18 hydrogen atoms were introduced. The chemical formula of the quantum clot is H18C51X, where X is the symbol of substitutional atom. The position of the localized levels is determined relative to the host atoms (C) epsilon(p) energies. We focused on the effect of substitutional doping by the B, N and O on the eigenstate energies and on the total energy change of the graphene dots including for O the effect of lattice distorsion. We conclude that B, N, and (O) can form stable substitutional defects in graphene quantum dot. (C) 2015 Elsevier B.V. All rights reserved