一个单分子磁铁对抗铁磁超交换合双核双 (III) 复合物的磁铁行为
Jérôme Long1, Fatemah Habib, Po-Heng Lin
1Department of Chemistry, University of Ottawa, 10 Marie-Curie, Ottawa, ON, K1N6N5, Canada.
Journal of the American Chemical Society
|March 24, 2011
概括
合成了五种新的兰化物复合物. 双 (III) 复合体表现出单分子磁体行为,显示出对理解磁放松机制至关重要的反铁磁合.
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:
- 兰化物复合物因其独特的磁性特性而受到研究.
- 单分子磁铁 (SMM) 对于开发高密度数据存储和量子计算至关重要.
- 了解二核兰坦化物系统中的磁交换相互作用是设计先进磁性材料的关键.
研究的目的:
- 合成和表征一系列的双核兰坦化物复合物.
- 研究这些复合物的磁性特性,特别是SMM行为.
- 阐明磁性交换合在散 (III) 复合体中的性质.
主要方法:
- 合成了五个双核胺复合物,其配方是[Ln(III) ((2) (((valdien) ((2) ((NO ((3)) ((2) ].
- 测量磁性特性,包括歇斯底里循环分析.
- 一开始的计算来确定交换合常数.
主要成果:
- 双核异 (III) 复合体 (4) 显示单分子磁体行为,具有 76 K 的有效异构屏障 (Ueff).
- 复合体4的hysteresis循环中的阶段状特征表明两个dysprosium离子之间的反铁磁交换合.
- 最初的计算证实了弱的反铁磁相互作用 (J ((Dy-Dy) = -0.21 cm ((-1))),与交换偏差的SMM行为一致.
结论:
- 合成的双核异 (III) 复合体是研究类系统中缓慢磁放松机制的有希望的候选者.
- 观察到的交换合提供了对具有可调节磁性特性的SMM设计的见解.
- 这项工作有助于对多核兰坦化物化合物中的磁相互作用的基本理解.
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