旋转和电荷的定位在基于烯的中性基导体中
Robert C Haddon1, Arindam Sarkar, Sushanta K Pal
1Department of Chemistry, University of California, Riverside, California 92521-0403, USA. haddon@ucr.edu
Journal of the American Chemical Society
|September 19, 2008
概括
基于烯基的基的结构分析揭示了非局部化的电子结构,而不是pi-dimers,驱动导电性变化. 这重新解释了这些分子导体的电子特性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 有机电子 有机电子
背景情况:
- 基于烯的中性基是分子导体的关键组成部分.
- 了解旋转和电荷定位对于它们的电子性质至关重要.
- 之前的研究表明,在一些激素中形成pi-dimer.
研究的目的:
- 实验分析基于烯的中性基分子导体中自旋和电荷定位的程度.
- 重新评估之前报告的烯基基的电子结构.
- 研究磁相转换期间增强导电性背后的机制.
主要方法:
- 开发基于实验的结构分析.
- 利用债券顺序和债券长度之间的关系.
- 在可变温度 (90 K到室温) 上对乙基 (1) 的单晶X射线衍射,通过磁相过渡 (~140 K) 观察结构和电子密度的变化.
主要成果:
- 在磁相转换时,二极性乙基 (1) 和丁基 (3) 的增强导电性是由于复杂的,高度非局部化的电子结构,而不是pi-dimer形成.
- 单质基 (4,12,13) 的电子密度分布不对称.
- 根基11是唯一被发现保持完全移位的单质根基;pi链根基 (7,8,14,15) 保持移位结构.
结论:
- 这项研究重新解释了基于烯的基因的电子结构,强调了非局部化而不是局部化的pi-dimer形成.
- 实验结构分析为分子导体的导电性机制提供了关键的见解.
- 这些发现需要对过去十年研究的众多烯基基的电子结构解释进行修订.
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