结构和磁性证据关于ru2 5+核心的formamidinate化合物中的旋转交叉
Panagiotis Angaridis1, F Albert Cotton, Carlos A Murillo
1Department of Chemistry and Laboratory for Molecular Structure and Bonding, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012, USA.
Journal of the American Chemical Society
|April 7, 2005
概括
两种与二甲胺连接体的二化合物表现出不同的磁性行为. 它们对温度变化的不同反应与电子配置和零场分裂效应有关.
科学领域:
- 无机化学 无机化学 有机化学
- 固态化学 固态化学
- 磁电化学 磁电化学 磁电化学
背景情况:
- 与结合的化合物具有独特的电子和磁性.
- 迪亚里尔形式胺连接物为调整这些性质提供了一个多功能平台.
- 了解结构属性关系对于设计新型磁性材料至关重要.
研究的目的:
- 为了研究两个不同的Ru2(DArF) 4Cl化合物的磁性和结构特性.
- 阐明控制这些复合体中磁性易感性温度依赖的因素.
- 为了将观察到的磁性行为与特定的电子配置和结构参数相关联.
主要方法:
- 合成和表征两种二甲基甲米丁复合物的合成和表征.
- 可变温度磁感应度 (chiT) 的测量.
- 取决于温度的X射线衍射来确定Ru-Ru键的长度.
主要成果:
- 和甲氨基替代化合物都表现出温度依赖的磁性易感性.
- 抛物质异构体在pi*3基和delta*pi*2兴奋状态之间显示了博尔兹曼分布,由不断变化的Ru-Ru键长度证明.
- 甲同位素保持了delta*pi*2配置,具有不变的Ru-Ru键长,但由于4B2u基本状态的零场分裂,chiT呈现下降.
结论:
- Ru2(DArF) 4Cl化合物的磁性对电子配置和替代物效应非常敏感.
- 结构变化,特别是Ru-Ru债券长度变化,可以直接与电子状态分布联系起来.
- 零场分裂为这些双核系统中温度依赖的磁性行为提供了替代机制.
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