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arXiv · 1506.04824

Phagraphene: A Low-energy Graphene Allotrope composed of 5-6-7 Carbon Rings with Distorted Dirac Cones

Zhenhai Wang·Xiang-Feng Zhou·Xiaoming Zhang·Qiang Zhu·Huafeng Dong·Mingwen Zhao·Artem R. Oganov
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Abstract

Using systematic evolutionary structure searching we propose a new carbon allotrope, phagraphene, standing for penta-hexa-hepta-graphene, because the structure is composed of 5-6-7 carbon rings. This two-dimensional (2D) carbon structure is lower in energy than most of the predicted 2D carbon allotropes due to its sp2-hybridization and density of atomic packing comparable to graphene. More interestingly, the electronic structure of phagraphene has distorted Dirac cones. The direction-dependent cones are further proved to be robust against external strain with tunable Fermi velocities.

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Zhenhai Wang, Xiang-Feng Zhou, Xiaoming Zhang, Qiang Zhu, Huafeng Dong, Mingwen Zhao, Artem R. Oganov. 2015-06-16. Phagraphene: A Low-energy Graphene Allotrope composed of 5-6-7 Carbon Rings with Distorted Dirac Cones. https://doi.org/10.1021/acs.nanolett.5b02512

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