通过提取电子的效应,在双核双单分子磁铁中显著增强了能量屏障
Fatemah Habib1, Gabriel Brunet, Veacheslav Vieru
1Chemistry Department, University of Ottawa , 10 Marie Curie, Ottawa, ON, K1N6N5, Canada.
Journal of the American Chemical Society
|August 23, 2013
概括
提取电子的配体显著增强了单分子磁铁 (SMM) 中的能量障碍. 化联体导致增长7倍,证明了开发先进磁性材料的强大战略.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 量子磁力 量子磁力 量子磁力 量子磁力
背景情况:
- 单分子磁铁 (SMM) 是具有缓慢磁性放松的分子材料.
- 控制能量屏障 (Ueff) 对于SMM性能至关重要.
- 连接体设计为调整SMM属性提供了一个有前途的途径.
研究的目的:
- 调查吸收电子的配体对二核二的能量屏障的影响 (III) SMMs.
- 为了合成和描述具有不同终端连接体的新型{Dy2} SMM.
- 为了建立一个结构-属性关系之间的连接物修饰和磁性行为.
主要方法:
- 合成了五种新的双核 {Dy2} 氧桥式SMM.
- 使用X射线衍射进行结构性表征.
- 测量磁性特性,包括直流 (dc) 和交流电 (ac) 易感性.
- Ab initio计算以确定电子结构和能源障碍.
主要成果:
- 系统地增强异型能量屏障,增加终端连接体的电子吸收特性.
- 对于含有化乙基酸连接体的复合物,观察到能量屏障增加了七倍 (6).
- Ab initio计算表明,在复合体4和6中,有更多的轴向g-tensors和更高的能量首先激发了克莱默斯双子,与增加的能量障碍相关.
结论:
- 提取电子的配体有效地显著提高了{Dy2} SMM 的能量屏障.
- 化连接体是最大限度地提高SMM性能的一种有效策略.
- 该研究为开发高性能分子磁性材料提供了对联体设计的宝贵见解.
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