一个稳定的五角形双金字塔Dy (III) 单离子磁铁,具有超过1000K的磁化逆转屏障
Jiang Liu1, Yan-Cong Chen1, Jun-Liang Liu1
1Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Sun Yat-Sen University , Guangzhou 510275, P. R. China.
Journal of the American Chemical Society
|April 8, 2016
概括
研究人员开发了新的单分子磁体 (SMM),其缓慢的磁放松和hysteresis循环高达14K.这些稳定的SMM实现了1025K的创纪录能量屏障,推进了分子磁性.
科学领域:
- 协调化学
- 材料科学
- 量子磁力学
背景情况:
- 单分子磁铁对于先进的磁性存储和量子计算至关重要.
- 开发具有较大的能量障碍和缓慢放松时间的稳定SMM仍然是一个重大挑战.
- 由于其固有的磁性特性,基于兰的SMM提供了有前途的途径.
研究的目的:
- 合成和描述具有SMM行为的新型,高度稳定的中性Dy (III) 协调化合物.
- 研究磁放松动力学,并确定导致缓慢放松的机制.
- 在分子系统中探索高温磁性歇斯底里的潜力.
主要方法:
- 合成具有五边形双金字塔形状的Dy(III) 协调化合物.
- 在未稀释的单晶上进行微SQUID测量,以探测弱分子间相互作用.
- 分析热激活的量子道和克拉默斯双重体的磁放松研究.
- 确定磁性异构和能量障碍
主要成果:
- 成功合成了两种具有五边形双金字塔协调的高度稳定的中性Dy(III) SMM.
- 在未稀释的单晶中观察到微弱的分子间相互作用,这对于单核兰坦化物SMM来说是一个新发现.
- 磁放松分析显示热激活的量子道通过第三激发克拉默斯双重体.
- 观察到高达14K的显着磁性歇斯底里循环.
- 突破有效能量障碍 (Ueff) 达到了1025K.
结论:
- 合成的Dy(III) 化合物代表了SMM领域的重大进步.
- 观察到的高能障碍和高达14K的歇斯底里表明它们具有高性能分子磁性的潜力.
- 这些发现突显了轴性磁性异构和弱分子间相互作用在设计高效的SMM中的重要性.
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