期刊
JOURNAL OF CHEMICAL PHYSICS
卷 133, 期 4, 页码 -出版社
AMER INST PHYSICS
DOI: 10.1063/1.3464479
关键词
-
资金
- National Natural Science Foundation of China [10979001]
- National Basic Research Program of China [2005CB724400]
- 2007 Cheung Kong Scholars Programme of China
- Changjiang Scholar and Innovative Research Team [IRT0625]
- National Fund for Fostering Talents of Basic Science [J0730311]
In this paper, we suggest a novel potential superhard material, a new carbon nitride phase consisted of sp(3) hybridized bonds, possessing a cubic P2(1)3 symmetry (8 atoms/cell, labeled by cg-CN) which is similar to cubic gauche nitrogen (cg-N) by first-principles calculations. It is a metallic compound, while most of other superhard materials are insulators or semiconductors. The Vickers hardness of cg-CN is 82.56 GPa, and if we considered the negative effect of metallic component on hardness, it is 54.7 GPa, which is much harder than any other metallic materials. It is found that a three-dimensional C-N network is mainly responsible for the high hardness. Both elastic constant and phonon-dispersion calculations show that this structure remains mechanically and dynamically stable in the pressure ranges from 0 to 100 GPa. Furthermore, we compared our results with many other proposed structures of carbon nitride with 1:1 stoichiometry and found that only cg-CN is the most favorable stable crystal structure. Formation enthalpies calculations demonstrate that this material can be synthesizable at high pressure (12.7-36.4 GPO. (C) 2010 American Institute of Physics. [doi:10.1063/1.3464479]
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据