多个轨道效应和磁性排序在一个中性根基中
Aaron Mailman1, Stephen M Winter, Joanne W L Wong
1Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada.
Journal of the American Chemical Society
|January 15, 2015
概括
用替代的bisdithiazolyl基IBBO表现出铁磁交换,作为一个旋转向的反铁磁体. 这种行为受到的旋转轨道效应的影响,导致净倾斜时刻.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 有机化学 有机化学
背景情况:
- 有机基质材料具有可调节的磁性.
- 了解磁交换相互作用对于设计分子磁铁至关重要.
- 重原子替代物的对磁性行为的影响需要进一步调查.
研究的目的:
- 为了研究替代 bisdithiazolyl 基 IBBO 的磁性特性.
- 阐明IBBO中铁磁交换和旋转转移背后的机制.
- 探索重原子效应和多轨道相互作用在磁性排序中的作用.
主要方法:
- 单晶X射线衍射以确定晶体结构 (空间组PNMA).
- 测量磁性易感度以确定磁性排序温度和参数.
- 对交换相互作用的分析,考虑同otropic,异otropic 和伪极极的贡献.
主要成果:
- IBBO 的 EtCN 溶解物呈现出一个交替的 ABABAB π 堆叠结构.
- 在π-堆上观察到铁磁交换相互作用.
- 材料订单作为一个旋转的反铁磁体,其 Néel 温度 (T(N)) 为 35 K.
- 测量了1.4×10-3μB的自发倾斜矩 (M(spont)) 和2K时1060Oe的强制场 (H(c)).
- 旋转曲线归因于多轨道贡献,并通过的旋转轨道效应得到增强.
- 伪极极相互作用会在c轴上诱导一个净倾斜的电流,并且很容易对a轴的亚晶格进行磁化.
结论:
- IBBO 的晶体结构和 π 堆叠使其能够进行强大的铁磁交换.
- 来自替代剂的旋转轨道合在使旋转转移成为可能方面发挥着至关重要的作用.
- 多轨道相互作用对于理解这个系统中同otropic 和 anisotropic 交换至关重要.
- IBBO代表了一种有希望的有机基材料,用于探索复杂的磁现象.
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