双核兰化物复合体中的f电子系统与phthalocyanines之间的相互作用
Naoto Ishikawa1, Tomochika Iino, Youkoh Kaizu
1Department of Chemistry, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8551, Japan. ishikawa@chem.titech.ac.jp
Journal of the American Chemical Society
|September 19, 2002
概括
这项研究揭示了双核兰化复合物与f(8) -f(10) 系统的铁磁相互作用,以及f(11) 系统的反铁磁相互作用. 这些f-f相互作用主要是由磁极二极子驱动的.
科学领域:
- 协调化学 协调化学
- 磁电化学 磁电化学 磁电化学
- 兰化物化学 兰化物化学
背景情况:
- 对于开发新型磁性材料来说,了解二核兰坦化物复合体中的f电子系统之间的相互作用至关重要.
- 聚氨酸联体为构建具有可调节电子性质的复合体提供了一个多功能平台.
研究的目的:
- 为了研究和描述二核性偏磁三价兰坦化物复合物的f-f相互作用.
- 探索f电子数量与磁相互作用的性质 (铁磁与反铁磁) 之间的关系.
主要方法:
- 同型核 ([Ln,Ln]) 和异型核 ([Ln,Y]) 兰酸酸复合物的合成.
- 从1.8K到室温的摩尔磁感应度的测量.
- 使用磁感应度和1H NMR数据确定连接体场参数.
主要成果:
- 在[Tb,Tb],[Dy,Dy]和[Ho,Ho]复合体 (f(8) -f(10) 中观察到铁磁f-f相互作用,相互作用强度随f电子数增加.
- 在[Er,Er] (f(11)) 和[Tm,Tm]复合体中发现了抗铁磁f-f相互作用.
- [Yb,Yb]复合体表现出可以忽略不计的f-f相互作用.
结论:
- 这些双核兰化复合物的f-f相互作用的性质和强度强烈依赖于f-电子的数量.
- 磁二极子被确定为观察到的f-f相互作用的主要贡献者.
- 这项研究提供了对以兰坦化为基础的分子系统中磁性合的基本见解.
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