Hexagonal diamond formation mechanism: A review

Yu Tao; Zhu Shengcai

doi:10.1063/5.0310909

Volume 11 Issue 3

May 2026

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Yu Tao, Zhu Shengcai. Hexagonal diamond formation mechanism: A review[J]. Matter and Radiation at Extremes, 2026, 11(3): 033801. doi: 10.1063/5.0310909

Citation:

Yu Tao, Zhu Shengcai. Hexagonal diamond formation mechanism: A review[J]. Matter and Radiation at Extremes, 2026, 11(3): 033801. doi: 10.1063/5.0310909

Yu Tao, Zhu Shengcai. Hexagonal diamond formation mechanism: A review[J]. Matter and Radiation at Extremes, 2026, 11(3): 033801. doi: 10.1063/5.0310909

Citation:

Yu Tao, Zhu Shengcai. Hexagonal diamond formation mechanism: A review[J]. Matter and Radiation at Extremes, 2026, 11(3): 033801. doi: 10.1063/5.0310909

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Hexagonal diamond formation mechanism: A review

doi: 10.1063/5.0310909

Yu Tao,
Zhu Shengcai^{,
,}

School of Materials, Sun Yat-sen University, Shenzhen, China

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Corresponding author: a)Author to whom correspondence should be addressed: zhushc@mail.sysu.edu.cn
Received Date: 2025-11-05
Accepted Date: 2026-03-03

Available Online: 2026-05-01

Publish Date: 2026-05-28

Abstract

Abstract

As a metastable carbon allotrope, hexagonal diamond (HD) exhibits potentially superior mechanical properties to cubic diamond (CD). However, its synthesis faces significant thermodynamic and kinetic challenges. This review summarizes the critical role of computational simulations in the synthesis of HD, covering both static calculations and molecular dynamics (MD) simulations. Static calculations reveal that graphite tends to transform into CD under interface-free conditions, whereas the presence of an interface results in a lower energy barrier for the HD phase transition. With regard to MD simulations, while early shock compression simulations failed to observe HD formation, recent studies based on neural network potentials have confirmed a shock-velocity-dependent transformation pathway and have successfully obtained HD, consistent with in situ experimental results. Hydrostatic pressure simulations emphasize the importance of controlling interlayer sliding, demonstrating that strategies such as quasi-uniaxial compression can promote the preferential formation of HD. In the future, the integration of high-precision simulations with experimental approaches is expected to enable the controllable synthesis of HD, thereby advancing its applications in ultrahard materials, power electronics, aerospace, and other fields.

Conflict of Interest
The authors have no conflicts to disclose.
Tao Yu: Data curation (equal); Formal analysis (equal); Investigation (equal). Shengcai Zhu: Conceptualization (equal); Funding acquisition (equal); Investigation (equal); Methodology (equal); Project administration (equal); Resources (equal); Software (equal); Supervision (equal).
Author Contributions
Data sharing is not applicable to this article as no new data were created or analyzed in this study.

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References(68)

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