富勒基铁磁体Eu3C70和Eu9C70的合成,结构和磁性特性
Taishi Takenobu1, Dam H Chi, Serena Margadonna
1Institute for Materials Research, Tohoku University, Katahira, Sendai 980-8577, Japan.
Journal of the American Chemical Society
|February 13, 2003
概括
欧与C ((70)) 富勒烯的间歇反应产生了两个磁性化合物:一种反铁磁体和一种铁磁体. 铁磁体的过渡温度为38K,相当于二元欧洲磁体的过渡温度.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 化学 化学 化学
背景情况:
- 像C70这样的富勒伦可以容纳客原子,从而产生新的材料性质.
- 欧 (Eu) 是一种稀土元素,以其磁性特性而闻名,特别是在其双价态 (Eu2+) 中.
研究的目的:
- 合成和描述通过将欧插入到C(70) 富勒中形成的磁性化合物.
- 研究这些新型欧-碳化合物的磁性和晶体结构.
主要方法:
- 合成欧交的C ((70)) 化合物.
- 测量磁性易感度以确定磁性排序和过渡温度.
- 用X射线衍射分析晶体结构.
主要成果:
- 合成了两种磁性化合物:Eu(x) C(70) (x ≈ 3) 作为一个倾斜的反铁磁体 (T(C) = 5 K) 和Eu(x) C(70) (x ≈ 9) 作为一个铁磁体 (T(C) = 38 K).
- 这两种化合物都表现出与Eu(2+) 离子一致的磁性行为.
- 铁磁的Eu{9-δ) C{70) 具有一个fcc结构的八面孔中的Eu{2+) 的立方体集群.
- 欧9-δ) C70的高过渡温度归因于短的欧2+) -欧2+) 距离和高的协调数.
结论:
- 欧与C{70) 的间隙形成了具有可调节性质的新磁性材料.
- 富勒主体的结构显著影响磁相互作用和过渡温度.
- 欧洲交叠的富勒烯显示出有前途的磁性材料,有可能在低温磁力中应用.
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