Hardness of T-carbon: Density functional theory calculations

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	Hardness of T-carbon: Density functional theory calculations
	X. Q. Chen; H. Y. Niu; C. Franchini; D. A. Z. Li; Y. Y. Li
	2011
发表期刊	Physical Review B
ISSN	1098-0121
卷号	84 期号:12
摘要	We reconsider and interpret the mechanical properties of the recently proposed allotrope of carbon, T-carbon [Sheng et al., Phys. Rev. Lett. 106, 155703 (2011)], using density functional theory in combination with different empirical hardness models. In contrast with the early estimation based on Gao et al.'s model, which attributes to T-carbon a high Vickers hardness of 61 GPa comparable to that of superhard cubic boron nitride (c-BN), we find that T-carbon is not a superhard material, since its Vickers hardness does not exceed 10 GPa. Besides providing clear evidence for the absence of superhardness in T-carbon, we discuss the physical reasons behind the failure of Gao et al.'s and Simunek and Vackar's (SV) models in predicting the hardness of T-carbon, residing in their improper treatment of the highly anisotropic distribution of quasi-sp(3)-like C-C hybrids. A possible remedy for the Gao et al. and SV models based on the concept of the superatom is suggested, which indeed yields a Vickers hardness of about 8 GPa.
部门归属	[chen, xing-qiu; niu, haiyang; franchini, cesare; li, dianzhong; li, yiyi] chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china. [franchini, cesare] univ vienna, fac phys, vienna, austria. [franchini, cesare] univ vienna, ctr computat mat sci, vienna, austria.;chen, xq (reprint author), chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china;xingqiu.chen@imr.ac.cn
关键词	Superhard Rhenium Diboride Elastic-constants Ambient-pressure Metal Borides Crystals Diamond Search Boron
URL	查看原文
WOS记录号	WOS:000295007400002
引用统计	被引频次：152[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/30266
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	X. Q. Chen,H. Y. Niu,C. Franchini,et al. Hardness of T-carbon: Density functional theory calculations[J]. Physical Review B,2011,84(12).
APA	X. Q. Chen,H. Y. Niu,C. Franchini,D. A. Z. Li,&Y. Y. Li.(2011).Hardness of T-carbon: Density functional theory calculations.Physical Review B,84(12).
MLA	X. Q. Chen,et al."Hardness of T-carbon: Density functional theory calculations".Physical Review B 84.12(2011).