中国物理B ›› 2017, Vol. 26 ›› Issue (4): 46303-046303.doi: 10.1088/1674-1056/26/4/046303

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

The electronic, optical, and thermodynamical properties of tetragonal, monoclinic, and orthorhombic M3N4 (M=Si, Ge, Sn): A first-principles study

Dong Chen(陈东), Ke Cheng(程科), Bei-Ying Qi(齐蓓影)   

  1. 1 College of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000, China;
    2 College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu 610025, China
  • 收稿日期:2016-12-25 修回日期:2017-01-19 出版日期:2017-04-05 发布日期:2017-04-05
  • 通讯作者: Dong Chen E-mail:chchendong2010@163.com
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61475132 and 61501392).

The electronic, optical, and thermodynamical properties of tetragonal, monoclinic, and orthorhombic M3N4 (M=Si, Ge, Sn): A first-principles study

Dong Chen(陈东)1, Ke Cheng(程科)2, Bei-Ying Qi(齐蓓影)1   

  1. 1 College of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000, China;
    2 College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu 610025, China
  • Received:2016-12-25 Revised:2017-01-19 Online:2017-04-05 Published:2017-04-05
  • Contact: Dong Chen E-mail:chchendong2010@163.com
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61475132 and 61501392).

摘要: A detailed study of the M3N4 (M=Si, Ge, Sn) nitrides in their tetragonal, monoclinic and orthorhombic phases has been performed with the plane-wave pseudo-potential method combined with the quasi-harmonic approximation, including the phononic effects. We rationalize the main puzzle, i.e., the fundamental properties of these phases are unclear, by calculating the crystal structures, density of states, and optical properties. The direct band gaps of t-Ge3N4, m-Si3N4, and o-Ge3N4 benefit the opto-electrical properties. t-, m-, and o-Si3N4 can be used as refractive materials while m-M3N4 (M=Si, Ge, Sn) are optically transparent in the visible light region. Our results improve the understanding of the detailed electronic structures of all compounds, as well as the influences of electronic structure on their stabilities. Furthermore, we find that thermodynamic quantities are sensitive to structures and, therefore, depend on various temperature and pressure conditions.

关键词: first-principles, density of states, optical properties, nitrides

Abstract: A detailed study of the M3N4 (M=Si, Ge, Sn) nitrides in their tetragonal, monoclinic and orthorhombic phases has been performed with the plane-wave pseudo-potential method combined with the quasi-harmonic approximation, including the phononic effects. We rationalize the main puzzle, i.e., the fundamental properties of these phases are unclear, by calculating the crystal structures, density of states, and optical properties. The direct band gaps of t-Ge3N4, m-Si3N4, and o-Ge3N4 benefit the opto-electrical properties. t-, m-, and o-Si3N4 can be used as refractive materials while m-M3N4 (M=Si, Ge, Sn) are optically transparent in the visible light region. Our results improve the understanding of the detailed electronic structures of all compounds, as well as the influences of electronic structure on their stabilities. Furthermore, we find that thermodynamic quantities are sensitive to structures and, therefore, depend on various temperature and pressure conditions.

Key words: first-principles, density of states, optical properties, nitrides

中图分类号:  (First-principles theory)

  • 63.20.dk
71.20.-b (Electron density of states and band structure of crystalline solids) 74.25.Gz (Optical properties) 81.05.Je (Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides))