中国物理B ›› 2023, Vol. 32 ›› Issue (8): 86101-086101.doi: 10.1088/1674-1056/acd2bf

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Pressure-induced phase transition and electronic structure evolution in layered semimetal HfTe2

Mei-Guang Zhang(张美光)1,†, Lei Chen(陈磊)1, Long Feng(冯龙)1, Huan-Huan Tuo(拓换换)1, Yun Zhang(张云)1, Qun Wei(魏群)2,‡, and Pei-Fang Li(李培芳)3   

  1. 1. College of Physics and Optoelectronic Technology, Collaborative Innovation Center of Rare-Earth Functional Materials and Devices Development, Baoji University of Arts and Sciences, Baoji 721016, China;
    2. School of Physics, Xidian University, Xi'an 710071, China;
    3. College of Mathematics and Physics, Inner Mongolia Minzu University, Tongliao 028043, China
  • 收稿日期:2023-03-17 修回日期:2023-04-17 接受日期:2023-05-05 发布日期:2023-07-24
  • 通讯作者: Mei-Guang Zhang, Qun Wei E-mail:zhmgbj@126.com;weiqunn@xidian.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No.11964026) and the Natural Science Basic Research Plan in Shaanxi Province of China (Grant Nos.2023-JC-YB-021,2022JM-035, and 2022JQ-008).

Pressure-induced phase transition and electronic structure evolution in layered semimetal HfTe2

Mei-Guang Zhang(张美光)1,†, Lei Chen(陈磊)1, Long Feng(冯龙)1, Huan-Huan Tuo(拓换换)1, Yun Zhang(张云)1, Qun Wei(魏群)2,‡, and Pei-Fang Li(李培芳)3   

  1. 1. College of Physics and Optoelectronic Technology, Collaborative Innovation Center of Rare-Earth Functional Materials and Devices Development, Baoji University of Arts and Sciences, Baoji 721016, China;
    2. School of Physics, Xidian University, Xi'an 710071, China;
    3. College of Mathematics and Physics, Inner Mongolia Minzu University, Tongliao 028043, China
  • Received:2023-03-17 Revised:2023-04-17 Accepted:2023-05-05 Published:2023-07-24
  • Contact: Mei-Guang Zhang, Qun Wei E-mail:zhmgbj@126.com;weiqunn@xidian.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No.11964026) and the Natural Science Basic Research Plan in Shaanxi Province of China (Grant Nos.2023-JC-YB-021,2022JM-035, and 2022JQ-008).

摘要: Motivated by the recent experimental work, the pressure-induced structural transition of well-known two-dimensional (2D) 1T-HfTe2 was investigated up to 50 GPa through the advanced CALYPSO structure search technique combined with the first-principles calculations. Our calculations suggested that the 1T-HfTe2 will first transform to C2/m phase at 3.6 GPa with a volume reduction of 7.6% and then to P$\bar{{6}}$2m phase at 9.6 GPa with a volume collapse of 4.6%. The occurrences of 3D C2/m and P$\bar{{6}}$2m phases mainly originated from the enhanced Te-Te interlayer coupling and the drastic distortions of Hf-Te polyhedrons in P$\bar{{3}}$m1 phase under compression. Concomitantly, the coordination number of Hf atoms increased from six in P$\bar{{3}}$m1 to eight in C2/m and eventually to nine in P$\bar{{6}}$2m at elevated pressure. The metallic and semimetallic nature of C2/m and P$\bar{{6}}$2m phases were characterized, and the evidence of the reinforced covalent interactions of Te-Hf and Te-Te orbitals in these two novel high-pressure phases were manifested by the atom-projected electronic DOS and Bader charge.

关键词: transition metal dichalcogenides, pressure-induced phase transition, crystal structure, electronic structure

Abstract: Motivated by the recent experimental work, the pressure-induced structural transition of well-known two-dimensional (2D) 1T-HfTe2 was investigated up to 50 GPa through the advanced CALYPSO structure search technique combined with the first-principles calculations. Our calculations suggested that the 1T-HfTe2 will first transform to C2/m phase at 3.6 GPa with a volume reduction of 7.6% and then to P$\bar{{6}}$2m phase at 9.6 GPa with a volume collapse of 4.6%. The occurrences of 3D C2/m and P$\bar{{6}}$2m phases mainly originated from the enhanced Te-Te interlayer coupling and the drastic distortions of Hf-Te polyhedrons in P$\bar{{3}}$m1 phase under compression. Concomitantly, the coordination number of Hf atoms increased from six in P$\bar{{3}}$m1 to eight in C2/m and eventually to nine in P$\bar{{6}}$2m at elevated pressure. The metallic and semimetallic nature of C2/m and P$\bar{{6}}$2m phases were characterized, and the evidence of the reinforced covalent interactions of Te-Hf and Te-Te orbitals in these two novel high-pressure phases were manifested by the atom-projected electronic DOS and Bader charge.

Key words: transition metal dichalcogenides, pressure-induced phase transition, crystal structure, electronic structure

中图分类号:  (Theory of crystal structure, crystal symmetry; calculations and modeling)

  • 61.50.Ah
61.50.Ks (Crystallographic aspects of phase transformations; pressure effects) 71.20.-b (Electron density of states and band structure of crystalline solids) 71.18.+y (Fermi surface: calculations and measurements; effective mass, g factor)