在2,2'-二胺基基桥梁的迪兰化物复合物中对交换合和磁放松的替代作用
Colin A Gould, Edward Mu, Veacheslav Vieru1
1Theory of Nanomaterials Group, Katholieke Universiteit Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium.
Journal of the American Chemical Society
|December 16, 2020
概括
研究人员通过改变替代物调整了根基桥接兰坦化物复合物的磁性合. 在加多复合体中更强的合导致了高能量屏障,用于磁性松的单分子磁体.
科学领域:
- 协调化学
- 材料科学
- 磁力学
背景情况:
- 设计具有增强性能的单分子磁铁 (SMM) 需要对相关化合物的系统研究.
- 具有强磁合的多核化物复合物对于先进的磁性材料至关重要,但尚未得到充分研究.
- 根基桥接合物具有可调节的磁性.
研究的目的:
- 合成和磁性表征一系列的激素桥梁迪兰化物.
- 研究桥接连体替代剂对磁交换合的影响.
- 将磁性合与基于的单分子磁铁的性能相关联.
主要方法:
- 用各种替代剂合成的迪兰化物复合盐在桥接的2,2'-双胺上.
- 磁性表征包括磁性易感性和放松动态的测量.
- 对磁交换合常数 (J) 和能量障碍 (U_eff) 的分析.
主要成果:
- 在加多复合体中,磁交换合常数 (J_Gd-rad) 可以通过修改替代剂从-2.7到-11.1厘米-1调整.
- 取电子的替代物加强了交换合,而电子的捐赠组则削弱了它.
- 更强的J_Gd-rad与更大的热屏障 (U_eff),更高的温度磁性歇斯底里,以及较慢的松类型相关.
结论:
- 在dysprosium SMMs中的U_eff与相应的gadolinium复合物中的J_Gd-rad之间建立了线性相关性.
- 这种模型提供了对基结桥接分子的电子结构和设计原理的洞察.
- 这些发现为设计具有更高工作温度的SMM提供了明确的标准.
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