东北大学学报（自然科学版）

东北大学学报(自然科学版) ›› 2011, Vol. 32 ›› Issue (12): 1795-1798.DOI: -

• 论著 • 上一篇    下一篇

CaMnO_3和LaMnO_3的电子结构研究

朱林;李林;李忠虎;魏国柱;   

  1. 东北大学理学院;朝鲜理科大学物理系;
  • 收稿日期:2013-06-19 修回日期:2013-06-19 发布日期:2013-04-04
  • 通讯作者: -
  • 作者简介:-
  • 基金资助:
    国家重点基础研究发展计划项目(2011CB606404)

Study on electronic structures of CaMnO3 and LaMnO3

Zhu, Lin (1); Li, Lin (1); Ri, Chung-Ho (1); Wei, Guo-Zhu (1)   

  1. (1) School of Sciences, Northeastern University, Shenyang 110819, China; (2) Department of Physics, Korea University of Science, Pyongyang, Korea, People's Democratic Rep
  • Received:2013-06-19 Revised:2013-06-19 Published:2013-04-04
  • Contact: Li, L.
  • About author:-
  • Supported by:
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摘要： 密度泛函理论(DFT)方法通常难以处理强关联体系,而DFT+U方法的计算结果强烈地依赖于U的取值.利用一种混合了部分DFT交换关联势和非局域Hartree-Fock精确交换势的杂化泛函HSE方法,研究了钙钛矿锰氧化物的两个典型反铁磁绝缘体CaMnO3和LaMnO3的电子结构,分析了二者的能隙特征与Mn离子价态和磁有序态的关联.根据ZSA方案CaMnO3可划分为电荷转移型绝缘体.LaMnO3的能隙表现出各向异性特征,其中沿c轴方向及ab面内的自旋多数通道中能隙的Mott-Hubbard特征更为显著,而自旋少数通道显示出完全的电荷转移型特征.

关键词: 强关联, 钙钛矿锰氧化物, 第一性原理, 杂化泛函, 能隙特征

Abstract: Density function theory (DFT) method is difficult to treat strongly correlated system, while DFT + U produces U-dependent results. The electronic structures of two typical antiferromagnetic insulators CaMnO3 and LaMnO3 in perovskite manganese oxides were investigated by using the hybrid functional HSE, which combined the DFT exchange-correlation potential and the nonlocal Hartree-Fock exact exchange potential. The relationship among the energy gap nature, the valence states of Mn, the magnetic structure was discussed. The results showed that CaMnO3 is classified as charge-transfer insulator according to ZSA (Zaanen-Sawatzky-Allen) scheme. The energy gap of LaMnO3 shows anisotropic character, in which the Mott-Hubbard character is dominant along c axis and in spin-majority channel within ab plane, while the charge-transfer character is exhibited in spin-minority channel.

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