一个具有长放松时间的内分体单分子磁铁:DySc2N@C80
Rasmus Westerström1, Jan Dreiser, Cinthia Piamonteze
1Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
Journal of the American Chemical Society
|May 16, 2012
概括
失酸酸末富勒烯 (DySc(2) N@C(80) 的磁性表现出歇斯底里和放松现象. 用C(60) 稀释样品显著延长了4f电子放松时间.
科学领域:
- 固态化学 固态化学
- 磁力学 磁力学 是一种
- 纳米技术 纳米技术
背景情况:
- 内充烯化合物在充烯内封装原子或小分子.
- 基于的材料以其磁性特性而闻名.
- 了解磁放松对于数据存储和量子计算的潜在应用至关重要.
研究的目的:
- 为了研究DySc(2) N@C(80) 内充烯的磁性特性.
- 探索温度和磁场对其磁性的影响.
- 为了检查稀释对磁放松动态的影响.
主要方法:
- 在X射线磁圆二重化 (XMCD) 光谱学.
- 超导量子干扰装置 (SQUID) 磁计. 超导量子干扰装置 (SQUID) 磁计. 超导量子干扰装置 (SQUID) 磁计. 超导量子干扰装置 (SQUID) 磁计. 超导量子干扰装置 (SQUID) 磁计.
- 可变温度 (低至2K) 和可变磁场 (高达7T) 的测量.
主要成果:
- XMCD揭示了Dy (III) 离子的4f旋转和轨道时刻中的hysteresis.
- SQUID磁力测量显示磁性歇斯底里低于6K.
- 观察到热和非热磁放松.
- 用C ((60) 稀释将2K的零场4f电子放松时间延长到几个小时.
结论:
- DySc(2) N@C(80) 表现出复杂的磁性行为,包括歇斯底里和放松.
- 稀释是一种有效的策略,可以延长磁放松时间.
- 这些发现有助于对磁性内充烯有潜在应用的理解.
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