论文标题
爆炸引起的石墨转化为六边形钻石
Detonation-induced transformation of graphite to hexagonal diamond
论文作者
论文摘要
我们使用位于NS时间尺度上的原位同步加速器X射线衍射在引爆诱导的冲击条件下探索高度定向的热解石墨（HOPG）的结构演化。我们观察到在50 GPA以上的压力下观察到与最近的气枪实验的定性一致的压力。第一原理密度的功能计算表明，在单轴压缩下，向六角钻的过渡的能量屏障低于立方钻石。最后，未观察到Cutic Diamond形成的迹象，最高为70 GPA。
We explore the structural evolution of highly oriented pyrolytic graphite (HOPG) under detonation-induced shock conditions using in-situ synchrotron X-ray diffraction in the ns time scale. We observe the formation of hexagonal diamond (lonsdaleite) at pressures above 50 GPa, in qualitative agreement with recent gas gun experiments. First-principles density functional calculations reveal that under uniaxial compression the energy barrier for the transition towards hexagonal diamond is lower than cubic diamond. Finally, no indication of cubic diamond formation was observed up to >70 GPa.
