高强力旋转玻璃在异构Mo2FeB2-类型M1.5Mn1.5B2 (M=Mo,W) 中
Shola E Adeniji1, Alexei A Belik2, Takao Mori2,3
1Department of Chemistry, University of California, Riverside, California 92521, United States.
Journal of the American Chemical Society
|October 27, 2025
概括
新的磁性材料Mo1.5Mn1.5B2和W1.5Mn1.5B2表现出高强制性的自旋玻璃行为. 这些发现为具有独特磁性质的先进多功能材料铺平了道路.
科学领域:
- 材料科学
- 凝聚物质物理学
- 磁力学
背景情况:
- 具有旋转玻璃行为和硬磁性特性的磁性材料对于先进的应用至关重要.
- Mo2FeB2型结构以其强大的结构特性和作为变磁材料的潜力而闻名.
研究的目的:
- 合成和描述Mo2FeB2型结构中的新型磁性材料.
- 调查这些材料中的自旋玻璃行为与硬磁铁强制性之间的合.
- 通过实验和计算方法探索潜在的磁相互作用和异构性.
主要方法:
- 固态合成路径以实现单相Mo1.5Mn1.5B2和W1.5Mn1.5B2.
- 温度依赖和交流易感度测量以探测磁转变和旋转动态.
- 密度函数理论 (DFT) 计算以确定磁相互作用和磁晶异性.
主要成果:
- Mo1.5Mn1.5B2显示了高强制性 (Hc = 302.4 kA/m) 的旋转玻璃行为 (Tg = 29 K).
- W1.5Mn1.5B2表现出反入集群旋转玻璃行为 (Tg = 43 K) 和铁磁过渡 (70 K) 与强制性 (Hc = 175.1 kA/m).
- DFT计算显示了竞争的FM/AFM相互作用和有利于c轴的单轴MAE,与实验观测相关.
结论:
- Mo2FeB2型结构可以容纳具有结合自旋玻璃和硬磁特性的材料.
- Mo1.5Mn1.5B2和W1.5Mn1.5B2是有前途的多功能磁性材料.
- 这些发现扩大了Mo2FeB2类型材料的应用范围,超出了结构用途.
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