在单核八坐标 ((II) 复合体中的缓慢磁放松
Lei Chen1, Jing Wang, Jin-Mei Wei
1State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.
Journal of the American Chemical Society
|August 15, 2014
概括
研究人员发现了第一个八坐标单核复合体,表现出缓慢的磁放松,这是单分子磁铁的关键性质. 这种 (II) 复合体显示出开发新型磁性材料的潜力.
科学领域:
- 协调化学 协调化学
- 磁力学 磁力学 是一种
- 材料科学 材料科学 材料科学
背景情况:
- 单分子磁铁 (SMM) 对于先进的磁性应用至关重要.
- 关于SMM的研究通常集中在低坐标过渡金属复合体上.
- 之前没有任何八坐标过渡金属复合体表现出SMM特性.
研究的目的:
- 为了研究八坐标单核 ((II) 复合物的磁性特性.
- 为了确定高坐标复合体是否可以表现出缓慢的磁放松.
- 探索超越低坐标系统的新型SMM候选者.
主要方法:
- 一个单核,八坐标 ((II) -12-皇冠-4复合物的合成和特征: [Co ((II) ((12C4) 2) ] ((I3) 2 ((12C4) 4).
- 磁性研究包括测量磁场诱导的慢磁放松.
- 使用阿雷尼乌斯模型分析磁性放松时间.
主要成果:
- 合成的 (II) 复合体表现出一个很大的轴向零场分裂.
- 在低温下,在500 Oe的应用场下观察到 induced field 缓慢的磁放松.
- 磁放松时间产生了17.0 cm-1的能量屏障 (Ueff) 和1.5 × 10−6 s的预指数因子 (τ0) .
结论:
- 这项研究提供了第一个八坐标,单核3d金属复合物的例子,显示缓慢的磁放松.
- 这些发现扩大了潜在的单分子磁铁分子设计的范围.
- 高坐标复合体是开发新型磁性材料的可行候选者.
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