超硬B-C-N材料的电子结构、硬度和光学性质的第一性原理计算

本文基于密度泛函理论(DFT)的第一性原理平面波超软赝势方法计算了z-BC₂N和z-B₂CN的4种晶体结构的电子结构、硬度和光学性质。结果表明，z-BC₂N(2)为直接带隙半导体，其禁带宽度2.449 eV,z-BC₂N(1)为间接宽带隙半导体，其禁带宽度为3.381 eV,而z-B₂CN(1)和z-B₂CN(2)为导体；硬度结果显示z-BC₂N(1)、z-BC₂N(2)和z-B₂CN(1)为超硬材料。最后通过计算z-BC₂N基本光学函数与光子能量的关系表征了其光学性质。分析结果表明，z-BC₂N结构可以用作良好的耐磨材料和窗口耐热材料。

First-Principles Calculations on Electronic Structures,Hardness and Optical Properties of Superhard B-C-N Compounds

Electronic structure, hardness and optical properties of four crystal structures of z-BC₂N and z-B₂CN were studied in this paper by first-principles calculations of plane wave ultra-soft pseudo-potential method based on the density functional theory (DFT). Deep analysis of electronic structure was carried out, indicating that z-BC₂N(1) and z-BC₂N(2) are indirect and direct wide band gap semiconductor, and band gap are 3.381 eV and 2.449 eV respectively, but z-B₂CN(1) and z-B₂CN(2) are conductors. Furthermore z-BC₂N(1), z-BC₂N(2) and z-B₂CN(1) are superhard materials. Finally, the optical properties of z-BC₂N(1) and z-BC₂N(2) were analyzed by calculating the relationship between the basic optical function and photon energy of z-BC₂N. Those data indicate that z-BC₂N structures can be served as wear-resistant materials and high-temperature-resistant materials that used by control windows.