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Mechanism for direct graphite-to-diamond phase transition.

ABSTRACT: Using classical molecular dynamics with a more reliable reactive LCBOPII potential, we have performed a detailed study on the direct graphite-to-diamond phase transition. Our results reveal a new so-called "wave-like buckling and slipping" mechanism, which controls the transformation from hexagonal graphite to cubic diamond. Based on this mechanism, we have explained how polycrystalline cubic diamond is converted from hexagonal graphite, and demonstrated that the initial interlayer distance of compressed hexagonal graphite play a key role to determine the grain size of cubic diamond. These results can broaden our understanding of the high pressure graphite-to-diamond phase transition.

SUBMITTER: Xie H

PROVIDER: S-EPMC4120013 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Mechanism for direct graphite-to-diamond phase transition.

Xie Hongxian H Yin Fuxing F Yu Tao T Wang Jian-Tao JT Liang Chunyong C

Scientific reports 20140804

Using classical molecular dynamics with a more reliable reactive LCBOPII potential, we have performed a detailed study on the direct graphite-to-diamond phase transition. Our results reveal a new so-called "wave-like buckling and slipping" mechanism, which controls the transformation from hexagonal graphite to cubic diamond. Based on this mechanism, we have explained how polycrystalline cubic diamond is converted from hexagonal graphite, and demonstrated that the initial interlayer distance of c ...[more]

PMID: 25088720

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