中国物理B ›› 2013, Vol. 22 ›› Issue (5): 57103-057103.doi: 10.1088/1674-1056/22/5/057103

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Structural, magnetic, electronic, and elastic properties of face-centered cubic PuHx (x = 2, 3):GGA (LSDA) + U + SO

郭咏a, 艾娟娟a, 高涛a, 敖冰云b   

  1. a Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China;
    b Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907, China
  • 收稿日期:2012-10-30 修回日期:2012-12-25 出版日期:2013-04-01 发布日期:2013-04-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 20971114).

Structural, magnetic, electronic, and elastic properties of face-centered cubic PuHx (x = 2, 3):GGA (LSDA) + U + SO

Guo Yong (郭咏)a, Ai Juan-Juan (艾娟娟)a, Gao Tao (高涛)a, Ao Bing-Yun (敖冰云)b   

  1. a Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China;
    b Science and Technology on Surface Physics and Chemistry Laboratory, P.O. Box 718-35, Mianyang 621907, China
  • Received:2012-10-30 Revised:2012-12-25 Online:2013-04-01 Published:2013-04-01
  • Contact: Gao Tao, Ao Bing-Yun E-mail:gaotao@scu.edu.cn; aobingyun24@yahoo.com.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 20971114).

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摘要： We perform first-principles calculations to investigate the structural, magnetic, electronic, and mechanical properties of face-centered cubic (fcc) PuH2 and fcc PuH3 using the full potential linearized augmented plane wave method (FP-LAPW) with the generalized gradient approximation (GGA) and the local spin density approximation (LSDA) taking account of both relativistic and strong correlation effects. The optimized lattice constant a0= 5.371 Å for fcc PuH2 and a0= 5.343 Å for fcc PuH3 calculated in the GGA + sp (spin polarization) + U (Hubbard parameter) + SO (spin-orbit coupling) scheme are in good agreement with the experimental data. The ground state of fcc PuH3 is found to be slightly ferromagnetic. Our results indicate that fcc PuH2 is a metal while fcc PuH3 is a semiconductor with a band gap about 0.35 eV. We note that the SO and the strong correlation between localized Pu 5f electrons are responsible for the band gap of fcc PuH3. The bonds for PuH2 have mainly covalent character while there are covalent bonds in addition to apparent ionicity bonds for PuH3. We also predict the elastic constants of fcc PuH2 and fcc PuH3, which were not observed in the previous experiments.

关键词: plutonium hydride, density-functional theory, magnetic and elastic properties, metal-insulator transition

Abstract: We perform first-principles calculations to investigate the structural, magnetic, electronic, and mechanical properties of face-centered cubic (fcc) PuH2 and fcc PuH3 using the full potential linearized augmented plane wave method (FP-LAPW) with the generalized gradient approximation (GGA) and the local spin density approximation (LSDA) taking account of both relativistic and strong correlation effects. The optimized lattice constant a0= 5.371 Å for fcc PuH2 and a0= 5.343 Å for fcc PuH3 calculated in the GGA + sp (spin polarization) + U (Hubbard parameter) + SO (spin-orbit coupling) scheme are in good agreement with the experimental data. The ground state of fcc PuH3 is found to be slightly ferromagnetic. Our results indicate that fcc PuH2 is a metal while fcc PuH3 is a semiconductor with a band gap about 0.35 eV. We note that the SO and the strong correlation between localized Pu 5f electrons are responsible for the band gap of fcc PuH3. The bonds for PuH2 have mainly covalent character while there are covalent bonds in addition to apparent ionicity bonds for PuH3. We also predict the elastic constants of fcc PuH2 and fcc PuH3, which were not observed in the previous experiments.

Key words: plutonium hydride, density-functional theory, magnetic and elastic properties, metal-insulator transition

中图分类号:  (Strongly correlated electron systems; heavy fermions)

  • 71.27.+a
71.30.+h (Metal-insulator transitions and other electronic transitions) 71.70.Ej (Spin-orbit coupling, Zeeman and Stark splitting, Jahn-Teller effect)