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arXiv · 1101.5447

Non-local exchange effects in zigzag edge magnetism of neutral graphene nanoribbons

Jeil Jung
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Abstract

We study the role of non-locality of exchange in a neutral zigzag graphene nanoribbon within the $π$-orbital unrestricted Hartree-Fock approximation. Within this theory we find that the magnetic features are further stabilized for both the intra-edge and inter-edge exchange compared to mean field theories of zigzag ribbon based on local exchange (like the Hubbard model or the ab-initio Local Density Approximation). The inter-edge exchange produces an enhancement of the band-gap of the magnetic ground-state solutions. The effect of this enhanced exchange on the edge states can not be satisfactorily achieved by a local interaction with renormalized parameters.

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Jeil Jung. 2011-01-28. Non-local exchange effects in zigzag edge magnetism of neutral graphene nanoribbons. https://doi.org/10.1103/physrevb.83.165415

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