文献类型：期刊文献

英文题名：Mechanical properties and electronic structures of VC, V4C3 and V8C7 from first principles

作者：Wang, Bin[1,2];Liu, Ying[1,3];Ye, Jinwen[1]

第一作者：Wang, Bin;王斌

通讯作者：Wang, B[1]

机构：[1]Sichuan Univ, Sch Mat Sci & Engn, Chengdu 610065, Peoples R China;[2]Xinxiang Univ, Phys & Elect Engn Dept, Xinxiang 453003, Peoples R China;[3]Minist Educ, Key Lab Adv Special Mat & Technol, Chengdu 610065, Peoples R China

第一机构：Sichuan Univ, Sch Mat Sci & Engn, Chengdu 610065, Peoples R China

通讯机构：[1]corresponding author), Sichuan Univ, Sch Mat Sci & Engn, Chengdu 610065, Peoples R China.

年份：2013

卷号：88

期号：1

外文期刊名：PHYSICA SCRIPTA

收录：;EI(收录号：20132916501966);Scopus(收录号：2-s2.0-84879947810);WOS:【SCI-EXPANDED(收录号:WOS:000321430800011)】；

基金：We are thankful for the support provided by the National Natural Science Foundation of China (grant no. 51104103) and by the Sichuan Provincial Science Research Program of China (grant no. 2011GZ0114). We specially acknowledge software support by the State Key Laboratory of Polymer Materials Engineering of Sichuan University.

语种：英文

外文关键词：Density functional theory - Electronic structure - Hardness - Lattice constants - Lattice theory - Shear strain

摘要：The lattice parameters, elastic properties, electronic structures and hardness of VC, V4C3 and V8C7 were studied by means of the pseudo-potential plane-waves method using the density function theory (DFT). The present lattice parameters of VC, V4C3 and V8C7 agree well with other theoretical and experimental data. V4C3 and V8C7 have lower values than VC in bulk modulus, shear modulus and Young's modulus, respectively. According to the analysis of the density of states of VC, V4C3 and V8C7, it was found that a C vacancy leads to the emergence of new peaks near the Fermi level that give a negative contribution to the shear modulus. As the hardness cannot be calculated from DFT directly, a semi-empirical model was used to estimate the hardness. Based on the overlap populations and bond lengths obtained from DFT, the hardness values of VC, V4C3 and V8C7 were evaluated. Furthermore, VC has the highest hardness.