计算物理 ›› 2004, Vol. 21 ›› Issue (3): 373-376.

• 研究简报 • 上一篇    下一篇

Ca3Co2O6及其掺镍体系的电子结构计算

闵新民, 朱磊, 邢学玲   

  1. 武汉理工大学材料复合新技术国家重点实验室, 湖北 武汉 430070
  • 收稿日期:2003-03-17 修回日期:2003-09-11 出版日期:2004-05-25 发布日期:2004-05-25
  • 作者简介:闵新民(1953-),男,湖北,教授,博士,主要从事计算材料科学研究.
  • 基金资助:
    国家自然科学基金(20271040)资助项目

Electronic Structure of Ca3Co2O6 and Ni-doped Ones

MIN Xin-min, ZHU Lei, XING Xue-lingnd   

  1. Processing, Wuhan University of Technology, Wuhan 430070, China
  • Received:2003-03-17 Revised:2003-09-11 Online:2004-05-25 Published:2004-05-25

摘要: 用离散变分密度泛函方法(DFT-DVM)计算了钴酸盐Ca3Co2O6及其掺镍体系,讨论了电子结构,化学键等与热电性能之间的关系.结果表明,价带和导带主要由Co3d,Ni3d和O2p原子轨道贡献.价带和导带之间的能隙宽度表现出了半导体电子结构特征,且掺镍体系的能隙比不掺镍体系窄.掺镍体系的共价键和离子键都比不掺镍体系弱.由此得到,掺镍后体系的热电性能将有所改善.

关键词: 钴酸盐, 电子结构, 化学键, 热电性能

Abstract: The electronic structures of Ca3Co2O6 and Ni-doped ones are calculated using density functional and discrete variation method (DFT-DVM).The relation between electronic structure,chemical bond and thermoelectric property is discussed.The results indicate that the highest valence band (HVB) and the lowest conduction band (LCB)are mainly contributed from Co3d,Ni3d and O2p atomic orbitals.The property of semiconductor is shown from the gap between HVB and LCB.The gap of Ni-doped ones is less than that of Ca3Co2O6.The covalent and ionic bonds of Ni-doped ones are both weaker than those of Ca3Co2O6.The thermoelectric property may be improved from adding Ni element into the system of Ca3Co2O6.

Key words: cobaltite, electronic structure, chemical bond, thermoelectric property

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