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arXiv · 1009.1808

Structure and stability of graphene nanoribbons in oxygen, carbon dioxide, water, and ammonia

Ari P. Seitsonen·A. Marco Saitta·Tobias Wassmann·Michele Lazzeri·Francesco Mauri
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Abstract

We determine, by means of density functional theory, the stability and the structure of graphene nanoribbon (GNR) edges in presence of molecules such as oxygen, water, ammonia, and carbon dioxide. As in the case of hydrogen-terminated nanoribbons, we find that the most stable armchair and zigzag configurations are characterized by a non-metallic/non-magnetic nature, and are compatible with Clar's sextet rules, well known in organic chemistry. In particular, we predict that, at thermodynamic equilibrium, neutral GNRs in oxygen-rich atmosphere should preferentially be along the armchair direction, while water-saturated GNRs should present zigzag edges. Our results promise to be particularly useful to GNRs synthesis, since the most recent and advanced experimental routes are most effective in water and/or ammonia-containing solutions.

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Ari P. Seitsonen, A. Marco Saitta, Tobias Wassmann, Michele Lazzeri, Francesco Mauri. 2010-09-09. Structure and stability of graphene nanoribbons in oxygen, carbon dioxide, water, and ammonia. https://doi.org/10.1103/physrevb.82.115425

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