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arXiv · 0906.0688

Evidence for Graphene Edges Beyond Zigzag and Armchair

Pekka Koskinen·Sami Malola·Hannu Häkkinen
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Abstract

The edges of nanoscopic objects determine most of their properties. For this reason the edges of honeycomb carbon--always considered either zigzag- or armchair-like--need special attention. In this report we provide experimental evidence confirming a previous unexpected prediction: zigzag is a metastable edge, as its planar reconstruction lowers energy and forms the most stable graphene edge. Our evidence is based on re-analyzing a recent experiment. Since the reconstructed edge, along with other unconventional edges we discuss, has distinct chemical properties, this discovery urges for care in experiments and theory--we must enter the realm beyond zigzag and armchair.

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Pekka Koskinen, Sami Malola, Hannu Häkkinen. 2009-06-03. Evidence for Graphene Edges Beyond Zigzag and Armchair. https://doi.org/10.1103/physrevb.80.073401

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