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arXiv · 1302.0964

Graphene nanoflakes - structural and electronic properties

Agnieszka Kuc·Thomas Heine·Gotthard Seifert
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Abstract

The structures, cohesive energies and HOMO-LUMO gaps of graphene nanoflakes and corresponding polycyclic aromatic hydrocarbons for a large variety of size and topology are investigated at the density functional based tight-binding level. Polyacene-like and honeycomb-like graphene nanoflakes were chosen as the topological limit structures. The influence of unsaturated edge atoms and dangling bonds on the stability is discussed. Our survey shows a linear trend for the cohesive energy as function of Ns/N (N - total number of atoms and Ns is number of edge atoms). For the HOMO-LUMO gap the trends are more complex and include also the topology of the edges.

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Agnieszka Kuc, Thomas Heine, Gotthard Seifert. 2013-02-05. Graphene nanoflakes - structural and electronic properties. https://doi.org/10.1103/physrevb.81.085430

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