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arXiv · 1105.0977

T-Carbon: A Novel Carbon Allotrope

Xian-Lei Sheng·Qing-Bo Yan·Fei Ye·Qing-Rong Zheng·Gang Su
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Abstract

A structurally stable crystalline carbon allotrope is predicted by means of the first-principles calculations. This allotrope can be derived by substituting each atom in diamond with a carbon tetrahedron, and possesses the same space group Fd^1 3m as diamond, which is thus coined as T- carbon. The calculations on geometrical, vibrational and electronic properties reveal that T-carbon, with a considerable structural stability and a much lower density 1.50 g/cm3, is a semiconductor with a direct band gap about 3.0 eV, and has a Vickers hardness 61.1 GPa lower than diamond but comparable with cubic boron nitride. Such a form of carbon, once obtained, would have wide applications in photocatalysis, adsoption, hydrogen storage and aerospace materials.

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Xian-Lei Sheng, Qing-Bo Yan, Fei Ye, Qing-Rong Zheng, Gang Su. 2011-05-05. T-Carbon: A Novel Carbon Allotrope. https://doi.org/10.1103/physrevlett.106.155703

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