The Structure of Terbium in the Ferromagnetic State
The Structure of Terbium in the Ferromagnetic State
复制标题
DOI：
10.1021/jacs.3c04931
复制
发表时间：
2023
影响因子：
15
通讯作者：
Xianran Xing
中科院分区：
文献类型：
--
作者：
Kun Lin;Guodong Li;Sergii Khmelevskyi;Leonid V. Pourovskii;Suihe Jiang;Kenichi Kato;Chengyi Yu;Yili Cao;Qiang Li;Xiaojun Kuang;Xianran Xing
Metals typically crystallize in highly symmetric structures due to their nondirectional and nonsaturated metallic bonds. Here, we report that terbium metal in its ferromagnetic state adopts an unusual low-symmetry orthorhombic structure with a Cmcm space group. A similar structure has been previously observed only in a few actinide metals with bonding 5f electrons at ambient pressure, such as uranium, neptunium, and plutonium, but with different nearest coordination numbers and bond-length variations. The Tb atom occupies the 4c site (0, ∼0.1661, 1/4), building up -[Tb-Tb]- layers stacking along the b-axis. Our first-principles many-body calculations of the crystal field splitting in the correlated Tb 4f-shell demonstrate that the Cmcm structure for ferromagnetic terbium is stabilized by magneto-elastic forces due to a secondary order of quadrupolar moments in the ferromagnetic state. These findings are significant for further understanding of the nature of terbium, including its electron structure, energy bands, phonons, and magnetism.
