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Chemical Vapor Deposition of an Organic Magnet, Vanadium Tetracyanoethylene
Published on: July 3, 2015
在富勒烯电荷转移盐 (TDAE) 中自发磁性排序C6060
Science (New York, N.Y.)
|March 24, 1995
概括
研究人员观察到16.1K以下的 (四氧化二甲胺乙烯) C(60) [TDAE) C(60) 中的自发磁顺序. 这种有机材料表现出铁磁性行为,达到比以前记录的类似化合物更高的基里温度.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 有机电荷转移盐具有独特的电子和磁性.
- 富勒烯衍生物由于其电子结构和潜在的应用而引起人们的兴趣.
- 了解新型有机材料中的磁顺序对于开发先进的电子设备至关重要.
研究的目的:
- 直接观察和描述 (四基二甲氨基乙烯) C(60) [TDAE) C(60) 中的自发磁顺序.
- 为了确定这种富勒烯盐的磁转换温度 (库里温度,T(c)).
- 为了研究材料内的磁性排序和激发的性质.
主要方法:
- 使用了零场子自旋放松 (μSR) 技术.
- 在冷温度下进行的测量,特别是低于可疑的磁过渡.
- 分析了内部磁场的温度依赖性及其空间分布.
主要成果:
- 直接观测自发磁顺序低于约16.1凯尔文的基里温度 (T(c)).
- 在 3.2 凯尔文的子位置测量了 68 (((1) 高斯的局部场,表明电子磁矩的连贯排序.
- 观察到实质性的空间不均效应,局部场分布宽度为48...2) 高斯在3.2凯尔文.
- 内部磁场的温度演变遵循集体自旋波 (马格农) 激发所期望的行为.
结论:
- [四二甲基胺乙烯]C(60) [TDAE) C(60) 富勒盐的铁磁状态低于16.1K.
- 这种材料达到比任何其他已知的有机材料都高的基里温度.
- 这些发现验证了过渡到铁磁状态的真实性,并提供了关于有机系统中磁激发的见解.
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