双 (III) 玻利复合物的强轴性导致65K的磁性阻塞
Alexandre H Vincent1, Yasmin L Whyatt2, Nicholas F Chilton2
1Department of Chemistry, University of California, Berkeley, Berkeley, California94720, United States.
Journal of the American Chemical Society
|January 11, 2023
概括
研究人员开发了一种新的dysprosium化合物,[K(18-crown-6) ][Dy(BC4Ph5) 2 ,它可以作为高性能单分子磁铁. 这种材料具有高达65K的磁性存储,超过了许多现有的基于的磁体.
科学领域:
- 协调化学
- 材料科学
- 磁性
背景情况:
- 替代的dysprosocenium复合体是已知的单分子磁体 (SMM),因为它们具有强大的轴联体场.
- 开发具有增强轴度的SMM是实现更高工作温度和保持磁性内存的关键.
研究的目的:
- 合成和表征一种新型的二 () 化合物,[K18-皇冠-6) ][DyBC4Ph5) 2 (1).
- 评估其作为单分子磁铁的性能,并与现有的dysprosocenium类似物进行比较.
主要方法:
- 合成和表征二 () 复合物.
- 测量可变磁场以评估磁性歇斯底里.
- 确定放松动态的交流磁感应性研究 (奥巴赫,拉曼,量子道).
- 开始时用于理论验证的旋转动态计算.
主要成果:
- 化合物1呈现高达66K的开放磁歇斯底里, 标识其为性能最高的SMM.
- 记录了65K的100秒阻塞温度,这是基于dysprosium的SMM中最高的.
- 实验放松参数 (Ueff=1500~100) cm-1,t0=10~12.0~9) s) 通过理论计算得到证实.
结论:
- 双乙烯 (borolide) 化合物1显示出优异的SMM性能,接近双乙烯类型的性能.
- 五甲基化物联体提供的伪轴协调环境有助于其高性能.
- 这项工作推动了用于更高温度应用的增强轴性SMM的开发.
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