在同结构重原子基中增强导电性和磁性排序
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
|June 6, 2008
概括
这项研究合成了新型异环状/基,揭示了含量增加增强导电性,并导致独特的磁性排序,包括某些化合物的铁磁性行为. 这些发现为有机材料提供了洞察力,这些有机材料具有可调节的电子和磁性质.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 有机电子 有机电子
背景情况:
- 共振稳定的异环基因基因由于其电子和磁性特性而引起人们的兴趣.
- 调节元素组成,特别是与等更重的原子,可以显著改变材料特性.
研究的目的:
- 合成和描述一系列完整的异环/基.
- 调查结合对这些基的结构性,导电性和磁性特性的影响.
主要方法:
- 合成异环状/基 (1a-4a).
- 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.
- 扩展的Hückel理论带结构计算.
主要成果:
- 这四种激素都是同结构的,具有滑动的pi-stack数组与分子间E2---E2'接触.
- 电导率随着含量增加而增加,在全基上达到3.0×10−4 S cm−1.
- 在低温下观察到磁性排序,在E2位置 (T (c) =12.8-17.0 K) 的含基中观察到铁磁性行为.
- 激活能量随着含量增加而下降.
结论:
- 的含量和位置极大地影响了这些异环基的电子和磁性特性.
- 观察到的磁顺序,特别是强烈的铁磁行为,表明了分子磁力学中的潜在应用.
- 该研究提供了对这种有机材料类的结构性质关系的全面了解.
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