摘要
为了研究不同压力下c-BN的力学性质、电子结构以及光学性质的变化,基于密度泛函理论构建了不同压力下c-BN的晶体模型.发现c-BN在不同压力下均力学稳定,随着压力增加,c-BN的弹性常数逐渐增大,材料的可压缩性逐渐变差;c-BN在零压下的禁带宽度为4.367 eV,表明c-BN是间接宽带隙半导体,随着压力增加,c-BN的禁带宽度逐渐增大,态密度谱图变化不明显;对Milliken布居分布在不同压力下进行分析,表明随着压力增加,B、N原子杂化后形成的B-N共价性增强.对c-BN的复介电函数、折射率、反射率等进行分析,发现随着压力增大,它们都产生一定蓝移,且在整个可见光谱范围以及红外与紫外(约从204 nm开始)光谱的很大范围内都透明.研究结果对高压下c-BN的应用有一定参考价值.
In order to research the changes of mechanical properties,electronic structure and optical properties of c-BN at different pressures,a crystal model of c-BN at different pressures was constructed based on density functional theory.It is found that c-BN is mechanically stable at different pressures,and theelastic constants of c-BN gradually increases with the increase of pressure,and the compressibility of the material gradually deteriorates;the forbidden band width of c-BN at zero pressure is 4.367 eV,indicating that c-BN is an indirect wide bandgap semiconductor,the forbidden band width of c-BN gradually increases,but the change of state density spectra is not obvious with the increase of pressure.Analysis of Milliken Boujou distribution at different pressures shows that with increasing pressure,the B-N covalency formed after hybridization of B and N atoms is enhanced.The analysis of the complex dielectric function,refractive index,and reflectivity of c-BN showed that they all produce a certain blue shift with increasing pressure and are transparent throughout the entire visible spectral range as well as a wide range of the infrared and ultraviolet(starting from about 204 nm)spectra.The results are valuable for the application of c-BN under high pressure.
作者
孙雪苗
刘红宇
贾睿
姜苏
SUN Xue-Miao;LIU Hong-Yu;JIA Rui;JIANG Su(School of Petrochemical Engineering,Shenyang University of Technology,Liaoyang 111003,China)
出处
《原子与分子物理学报》
CAS
北大核心
2021年第5期115-122,共8页
Journal of Atomic and Molecular Physics
关键词
C-BN
力学性质
第一性原理
电子结构
光学性质
c-BN
Mechanical properties
First-principle
Electron structure
Optical properties
