Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
J Chem Phys. 2017 Aug 14;147(6):064512. doi: 10.1063/1.4986164.
We identify by ab initio calculations a new simple cubic carbon phase in Pa3¯ symmetry, which has a 48-atom unit cell in all-sp bonding networks, thus termed SC48 carbon. It can be viewed as a crystalline form of C clusters or a combined structure of SC24 and BC12 carbon, but it is energetically more stable than the recently reported cubic carbon phases such as BC8, SC24, BC12, and fcc-C. The structural stability is verified by phonon mode analysis. Electronic band and density of state calculations reveal that SC48 carbon is an insulator with a large direct band gap of 4.40 eV. Moreover, simulated x-ray diffraction patterns provide an excellent match to the distinct diffraction peaks found in milled fullerene soot. These results provide a solid foundation for further exploration of this new carbon allotrope.
我们通过从头算计算确定了一种新的具有 Pa3¯ 对称的简单立方碳相，它具有全 sp 键的 48 原子单位晶胞，因此称为 SC48 碳。它可以看作是 C 团簇的晶态形式或 SC24 和 BC12 碳的组合结构，但它比最近报道的立方碳相（如 BC8、SC24、BC12 和 fcc-C）更稳定。声子模式分析验证了结构稳定性。电子能带和态密度计算表明，SC48 碳是一种具有 4.40 eV 大直接带隙的绝缘体。此外，模拟的 X 射线衍射图谱与研磨富勒烯烟尘中发现的独特衍射峰提供了极好的匹配。这些结果为进一步探索这种新的碳同素异形体提供了坚实的基础。
