Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (02): 388-394.doi: 10.3866/PKU.WHXB20110220

• THEORETICAL AND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

Electronic and Band Structures of Hexagonal Multiferroic HoMnO3

ZHONG Chong-Gui1,2,3, FANG Jing-Huai1, YANG Jian-Hua1, DONG Zheng-Chao1,3, JIANG Xue-Fan2   

  1. 1. School of Sciences, Nantong University, Nantong 226007, Jiangsu Province, P. R. China;
    2. Jiangsu Key Laboratory of Advanced Functional Materials, Changshu Institute of Technology, Changshu, 215500, Jiangsu Province, P. R. China; 3School of Physical Sciences and Technology, Soochow University, Suzhou 215006, Jiangsu Province,P. R. China
  • Received:2010-08-02 Revised:2010-11-01 Published:2011-01-25
  • Contact: DONG Zheng-Chao, ZHONG Chong-Gui E-mail:dzc@ntu.edu.cn, chgzhong@ntu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (10974104, 50832002, 10874021, 30970754), Natural Science Foundation of Jiangsu Province, China (BK2006047, BK2008183), and Qing Lan Project of Education Department of Jiangsu Province, China.

Abstract:

We investigated the magnetism, electronic and band structures of hexagonal HoMnO3 using density functional theory (DFT) within the generalized gradient approximation (GGA) and combined this with the projector augmented wave (PAW) method. The relative experimental results are explained using non-collinear magnetic structure calculations. The calculations show that the total energy of the unit cell decreases and the energy gap as well as magnetic moment of Mn3+ increases. Each atom coordinate was close to the experimentally measured values and the electronic densities of states of the HoMnO3 qualitatively agreed with the results from X-ray absorption spectroscopy, when the noncollinear triangular antiferromagnetic configurations of the Mn3+ ions in the ab plane were taken into account. According to the densities of states and band structure analysis, as calculated within the noncollinear magnetic structure, we found that the two experimentally determined optical absorption peaks near 1.7 and 2.3 eV were due to interband transitions between the oxygen states that hybridize strongly with different Mn orbitals and the Mn [3d3z2-r2] state. The strong orbital hybridization between Ho 5d and O(3, 4) 2p in the plane drives the ferroelectric polarization of the HoMnO3 to the ab plane.

Key words: Antiferromaget, Frustration, Magnetoelectricity, Hybridization, Ferroelectricity

MSC2000: 

  • O641.4