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Updated: Apr 5, 2026
09:13
Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
Published on: April 1, 2017
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Ab initio structure determination of n-diamond.
Da Li1,2, Fubo Tian1, Binhua Chu1
1State Key Lab of Superhard Materials, College of Physics, Jilin University, Changchun 130012, P. R. China.
Scientific Reports
|August 25, 2015
Summary
Researchers discovered a new carbon allotrope, HR-carbon, with potential applications as n-diamond. This novel material exhibits high stability and hardness comparable to diamond, attributed to its unique C3 isosceles triangle rings.
Area of Science:
- Materials Science
- Computational Chemistry
- Solid State Physics
Background:
- The search for novel carbon allotropes with superior properties to diamond is ongoing.
- Understanding the stability and mechanical properties of carbon structures under high pressure is crucial.
Purpose of the Study:
- To computationally investigate the crystal structure of a potential n-diamond candidate.
- To predict and characterize a novel carbon allotrope, named HR-carbon.
Main Methods:
- First-principle calculations were employed for systematic computational study.
- Simulations of X-ray diffraction, Raman, and energy-loss near-edge spectra were performed.
Main Results:
- A new hexagonal carbon allotrope, HR-carbon (space group R32), was predicted.
- HR-carbon, featuring lonsdaleite layers and C3 isosceles triangle rings, is stable above 14.2 GPa.
- Simulated spectra closely matched experimental data, supporting HR-carbon as a candidate for n-diamond.
- Calculated hardness (80 GPa) and bulk modulus (427 GPa) are comparable to diamond.
Conclusions:
- HR-carbon is a stable and hard carbon allotrope, potentially serving as n-diamond.
- The unique C3 isosceles triangle rings are key to HR-carbon's stability and mechanical strength.
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