Physical properties of B_4N_4-Ⅰ and B_4N_4-Ⅱ:First-principles study

作     者：Zhenyang Ma Peng Wang Fang Yan Chunlei Shi Yi Tian 马振洋;王鹏;阎芳;史春蕾;田毅

作者机构：Key Laboratory of Civil Aircraft Airworthiness TechnologyCivil Aircraft Airworthiness and Repair Key Laboratory of TianjinSchool of AirworthinessCivil Aviation University of China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2019年第28卷第3期

页      面：283-290页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.61601468) the Fundamental Research Funds for the Central Universities,China(Grant No.3122014C024) the Fund for Scholars of Civil Aviation of the University of China(Grant No.2013QD06X) 

主　　题：BN polymorphs mechanical properties electronic properties mechanical anisotropic properties 

摘      要：The structural, mechanical, electronic, mechanical anisotropy, and thermal properties of boron nitride(BN) polymorphs, such as B_4 N-4-Ⅰ and B4 N4-Ⅱ, are investigated under ambient pressure utilizing first-principles generalized gradient approximation calculations using an ultrasoft pseudopotential scheme. The phonon spectra and elastic constants reveal that B_4 N_4-Ⅰ is dynamically and mechanically stable at the pressure of 0 GPa and temperature of 0 K. Anisotropic calculations indicate that both B_4 N_4-Ⅰ and B4 N4-Ⅱ exhibit higher anisotropy of Young s modulus than cubic BN(c-BN). B_4 N_4-Ⅱ and B_4 N_4-Ⅰ present indirect and wide band gaps of 5.32 eV and 4.86 eV, respectively. In addition, B_4 N_4-Ⅰ is more brittle than B_4 N_4-Ⅱ. Moreover, the minimum thermal conductivity,κmin, of B4 N4-Ⅱ at 300 K is 1.92 W/(cm·K), which is slightly higher than those of B_4 N_4-Ⅰ and c-BN(1.84 W/(cm-K) and 1.83 W/(cm-K), respectively. However, κ_(min) of B_4 N_4-Ⅰ is slightly higher than that of c-BN.