一个有机金属构建块方法来生产一个多层4f单分子磁铁
Jennifer J Le Roy1, Matthew Jeletic, Serge I Gorelsky
1Chemistry Department and the Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada.
Journal of the American Chemical Society
|February 9, 2013
概括
研究人员探索了dysprosium复合物的磁性特性,创造了单离子磁铁 (SIM) 和单分子磁铁 (SMM). 删除大型组可以重新定位磁轴以提高性能.
科学领域:
- 协调化学 协调化学
- 磁电化学 磁电化学 磁电化学
- 计算化学的计算化学
背景情况:
- 有机金属构建块策略对于设计先进的磁性材料至关重要.
- 兰化物 (III) 复合物为开发单离子磁铁 (SIM) 和单分子磁铁 (SMM) 提供了潜力.
研究的目的:
- 合成和研究新的同质性Dy(III) COT′′2和Ln(III) 2COT′′3 (Ln = Gd, Dy) 复合物的磁性特性.
- 了解电子结构,分子几何学和磁性行为之间的关系在这些兰坦化物复合体中.
- 通过修改连接体结构来探索调整磁性质的潜力.
主要方法:
- 同质的Dy(III) COT′′2和Ln(III) 2COT′′3复合物的合成.
- 密度函数理论 (DFT) 计算分析金属-合体共价性和电子结构.
- 测量Ac易受性,以描述磁性特性 (SIM和SMM行为).
- Ab initio计算以确定磁性异构轴.
主要成果:
- 成功合成了Dy(III) COT′′2和Dy(III) 2COT′′3复合体.
- DFT计算显示,双金属Dy (III) 复合体中具有强烈的金属-连接体共价性和不均的电子捐赠.
- 证实Dy(III) COT′′2表现出SIM行为,而Dy(III) 2COT′′3表现出SMM行为.
- Ab initio计算显示,由于三甲基基组,磁性异构轴与COT′′环不垂直.
结论:
- 有机金属构建块策略是有效的创建基于胺的SIM和SMM.
- 分子结构,特别是大量替代物的存在,显著影响了磁性异质性.
- 预计去除三甲基基组将使异构轴的重新定位成为可能,为改善磁性性能提供了一条途径.
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