在bistiaselenazolyl基中铁磁排序:四角形主题的变化
Craig M Robertson1, Alicea A Leitch, Kristina Cvrkalj
1Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Journal of the American Chemical Society
|October 14, 2008
概括
合成和研究了五种新的异构贝斯蒂亚塞伦醇基. 它们的晶体结构揭示了与密切接触的滑落pi堆,影响了从反铁磁到铁磁的磁性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 同结构的比斯蒂亚斯-塞莱纳基激素为研究结构-性质关系提供了一个独特的平台.
- 了解分子间相互作用对于设计新型电子材料至关重要.
研究的目的:
- 为了合成和表征一系列同结构的bistiaselenazolyl基.
- 研究结构变异对分子间接触和磁性行为的影响.
- 为了阐明观测到的磁性秩序背后的机制.
主要方法:
- 用于结构确定的X射线晶体学.
- 可变温度导电性和磁感应度的测量.
- 密度函数理论 (DFT) 计算用于交换能量分析.
主要成果:
- 准备了五个同结构的bistiaselenazolyl基,在空间组P42(1)m中结晶,并使用滑过的pi-stack数组.
- 观察到分子间Se---Se'接触,受R1和R2替代物的变化影响.
- 导电性值在10(-5)-10(-4) S cm(-1) 之间,激活能量为0.27-0.31 eV.
- 磁性易感性揭示了从抗铁磁性到铁磁性顺序的切换 (T (c) ~13-14K) 与结构修改.
结论:
- 布斯蒂亚斯醇基的结构变化显著改变pi-stack滑动和分子间接触.
- 这些结构变化直接影响磁性交换相互作用,导致不同的磁性排序行为.
- DFT计算支持通过空间交换机制,将pi-stack滑动与反铁磁合强度相关联.
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