MA Qiuhua 1 , TIAN Junhui 2 , WANG Gaimin 1 , HOU Yonggai 1
（1.Department of Materials Science and Engineering, He'nan University of Technology, Zhengzhou Henan 450007,China;2.SSchool of Science, He'nan University of Technology, Zhengzhou Henan 450007, China）
Abstract: The electronic structures of superhard cubic C3N4 material were investigated by first-principles calculations with planewave pseudopotential method and generalized approximation (GGA) based on density functional theory (DFT). The results showed that cubic C3N4 is an indirect gap semiconductor and its band-gap energy is 2.92ev.The valence electron structures of C and N atoms are 2s1.022p2.54and 2s1.382p3.96, respectively. The bond length is 0.14771nm. The long-wavelength threshold for absorption is 147nm and the static dielectric constant is 4.6. The study revealed by calculation that cubic C3N4not only has high hardness, good thermal stability and chemical stability, but also excellent microwave and infrared penetrating. It provides guidance for applications in wear-resisting aspects and optical fields.
Key words: cubic C3N4; electronic structures; high temperature wear resistant; infrared penetrating