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Updated: Jun 2, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
T-carbon: a novel carbon allotrope
Xian-Lei Sheng1, Qing-Bo Yan, Fei Ye
1College of Physical Sciences, Graduate University of Chinese Academy of Sciences, P.O. Box 4588, Beijing 100049, China.
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 Fd3m 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, adsorption, hydrogen storage, and aerospace materials.
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