在共聚性结合的捐赠/接受链化合物中,逐步的中性-离子相过渡
Hitoshi Miyasaka1, Natsuko Motokawa, Tamiko Chiyo
1Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Sendai 980-8578, Japan. miyasaka@se.kanazawa-u.ac.jp
Journal of the American Chemical Society
|March 18, 2011
概括
这项研究揭示了由库伦相互作用驱动的金属复杂供体/受体链中的逐步中性离子过渡. 这种逐步的行为为控制充电和旋转功能提供了新的可能性.
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:
- 有机捐赠体 (D) /接受体 (A) 复合体中中性 (N) - 离子 (I) 转换具有多种功能.
- 控制这些转换需要调整电离潜力和电子亲和力.
- 库伦相互作用在阶段性N-I过渡中的作用尚不清楚.
研究的目的:
- 为逐步的N-I转换提供了明确的证据.
- 为了研究异型链间库伦相互作用的影响.
- 探索由此产生的自旋基态和磁顺序的变化.
主要方法:
- 一种基于金属复合物的共价键DA链化合物的合成和表征: [Ru(2)(2,3,5,6-F(4) PhCO(2))(4)(DMDCNQI) ]·2(p-xylen).
- 取决于温度的测量以观察相位过渡.
- 分析电荷,自旋和格子属性.
主要成果:
- 在中间温度范围 (210 K270 K) 中观察到渐进的N-I过渡.
- 在这个阶段确定了自组织的N和I链.
- 证明了离子阶段的自旋基状况和铁磁秩序的变化.
结论:
- 非同位素连锁库伦相互作用驱动阶段性N-I过渡.
- 阶段性过渡表现出高度敏感的磁反应.
- 这种现象为负责,旋转和格子系统的新动态功能开辟了道路.
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