Mechanism for direct graphite-to-diamond phase transition

نویسندگان

  • Hongxian Xie
  • Fuxing Yin
  • Tao Yu
  • Jian-Tao Wang
  • Chunyong Liang
چکیده

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.

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عنوان ژورنال:

دوره 4  شماره 

صفحات  -

تاریخ انتشار 2014