中国物理B ›› 2025, Vol. 34 ›› Issue (8): 87101-087101.doi: 10.1088/1674-1056/add4e6
所属专题： SPECIAL TOPIC — Structures and properties of materials under high pressure
Ab initio prediction of ground-state magnetic ordering and high-pressure magnetic phase transition of uranium mononitride
Jing-Jing Zheng(郑晶晶)1,†, Yuxi Chen(陈禹西)2,†, Chengxiang Zhao(赵承祥)2, Junfeng Zhang(张均锋)3,‡, Ping Zhang(张平)4, Bao-Tian Wang(王保田)5, and Jiang-Jiang Ma(马江将)2§
- 1 Department of Physics, Taiyuan Normal University, Jinzhong 030619, China;
2 School of Physics and Electronics Engineering, Shanxi Normal University, Taiyuan 030031, China;
3 College of Physics and Electronic Engineering, Hainan Normal University, Haikou 571158, China;
4 Institute of Applied Physics and Computational Mathematics, Beijing 100088, China;
5 Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, China
Ab initio prediction of ground-state magnetic ordering and high-pressure magnetic phase transition of uranium mononitride
Jing-Jing Zheng(郑晶晶)1,†, Yuxi Chen(陈禹西)2,†, Chengxiang Zhao(赵承祥)2, Junfeng Zhang(张均锋)3,‡, Ping Zhang(张平)4, Bao-Tian Wang(王保田)5, and Jiang-Jiang Ma(马江将)2§
- 1 Department of Physics, Taiyuan Normal University, Jinzhong 030619, China;
2 School of Physics and Electronics Engineering, Shanxi Normal University, Taiyuan 030031, China;
3 College of Physics and Electronic Engineering, Hainan Normal University, Haikou 571158, China;
4 Institute of Applied Physics and Computational Mathematics, Beijing 100088, China;
5 Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, China
摘要： The ground-state magnetic ordering of uranium mononitride (UN) remains a contentious topic due to the unexpected lack of crystallographic distortion in the traditionally accepted $1\bm{k}$ antiferromagnetic (AFM) state. This discrepancy casts doubt on the validity of the $1\bm{k}$ magnetic ordering of UN. Here, we investigate the crystal structure, high-pressure phase transitions, and dynamical and mechanical properties of UN in its $1\bm{k}$ and $3\bm{k}$ AFM ground states using density functional theory (DFT). Our results reveal that the undistorted $3\bm{k}$ AFM state of Fm$\overline{3}$m within the ${\rm DFT}+{U}+{\rm SOC}$ scheme is more consistent with experimental results. The Hubbard U and spin-orbit coupling (SOC) are critical for accurately capturing the crystal structure, high-pressure structural phase transition, and dynamical properties of UN. In addition, we have identified a new high-pressure magnetic phase transition from the nonmagnetic (NM) phase of R$\overline{3}$m to the P$6_{3}$/mmc AFM state. Electronic structure analysis reveals that the magnetic ordering in the ground state is primarily linked to variations in partial 5f orbital distributions. Our calculations provide valuable theoretical insights into the complex magnetic structures of a typical strongly correlated uranium-based compound. Moreover, they provide a framework for understanding other similar actinide systems.
中图分类号: (Density functional theory, local density approximation, gradient and other corrections)
- 71.15.Mb