合策略,以增强单分子磁铁性质的-环氧-烯复合物
Jennifer J Le Roy1, Liviu Ungur, Ilia Korobkov
1Department of Chemistry, University of Ottawa , 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada.
Journal of the American Chemical Society
|May 9, 2014
概括
研究人员开发了具有增强性能的新型单分子磁铁 (SMM). 这些新的SMM在低温下表现出磁性歇斯底里,显示出先进磁性应用的前景.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 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.
- 兰化物离子,特别是Er(III),由于它们的大磁矩和可调节性质,是SMM的有希望的候选物.
- 以前的研究集中在单核SMM上,但二维结构为增强磁性性能提供了潜力.
研究的目的:
- 通过两种不同的合策略,合成和描述新的Er(III) 双核复合体.
- 研究这些复合物的磁性特性,重点关注它们作为高阻塞温度SMM的潜力.
- 阐明分子结构,交换合和Er (III) 系统中的SMM行为之间的关系.
主要方法:
- 通过使用不同的合策略,合成兰化物-环氧甲乙烯 (COT) 复合物.
- 测量磁性特性,包括静态和动态磁性易感性.
- 在固态和溶液中分析磁性歇斯底里循环.
- 测量Ac易受性的测量以确定阻塞温度.
主要成果:
- 两种Er (III) 二核复合物[Er (III) 2 (COT') 3和K2 (THF) 4[Er (III) 2 (COT) ]4已经成功合成.
- 两个Er(III) 复合体都表现出SMM行为,在12K (固态) 和高达14K (溶液中的化合物1) 时观察到磁性歇斯底里.
- 两个复合体的阻塞温度分别为12.5K和12.9K.
- 与单核相似物相比,双核复合物显示出更好的SMM特性,这归因于它们的线性结构和轴性异构性.
- 阻断温度的显著增加与[Er(III) 2[COT'') 3之间的交换合有关.
结论:
- 采用的合策略成功生成了具有增强SMM特性的Er(III) 双核复合体.
- 线性结构和轴性异构性在提高SMM性能方面发挥着关键作用.
- 埃尔 (III) 离子之间的交换合提供了一个额外的磁化阻断机制,导致更高的阻断温度.
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