在四法 (TTF) 导体中以结合为辅助的自我兴奋剂
Yuka Kobayashi1, Mayu Yoshioka, Kazuhiko Saigo
1Waseda Institute for Advanced Study, Waseda University, Tokyo, 169-8050, Japan. yuka@aoni.waseda.jp
Journal of the American Chemical Society
|July 3, 2009
概括
氨四甲基二碳酸盐 (TTFCOO(-)NH(4)(+)) 通过质子化从绝缘体转变为自我补充导体. 结合促进了这种转变,创造了一种具有半导体特性的新"结合辅助自导体".
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:
- 甲 (TTF) 衍生物因其导电性质而被广泛研究.
- 在有机导体中实现受控的自我兴奋剂仍然是一个重大挑战.
- 了解分子间相互作用在调整电子特性中的作用至关重要.
研究的目的:
- 为了合成和表征四亚富二碳酸盐 (TTFCOO(-) NH(4) ((+)).
- 为了阐明这种自我兴奋导体的载体生成机制和分子轨道特征.
- 为了研究结对导电行为的影响.
主要方法:
- 从TTFCOOH中合成TTFCOO ((-) NH ((4) ((+)) 的合成.
- 使用紫外线,ESR和1H NMR光谱学进行表征.
- 用X射线晶体学来确定晶体结构.
- 分子轨道计算 (集群模型和初始周期计算).
- 测量电导率和同位素效应.
主要成果:
- 绝缘TTFCOOH转化为一个带孔的导体 (TTFCOO(-)NH(4)(+)) 导电性sigma=2.0 x 10(-4) S/cm在300 K.
- TTF部分的质子化产生了一个基物种 (TTF(*+) COO(-) NH(4) ((+)).
- X射线结构揭示了通过键连接的超分子TTFCOO(-) 阵列.
- 分子轨道计算表明,激素的准封闭外状态.
- 结合对电子导电有着显著的贡献,由一个大的同位素效应证明.
结论:
- TTFCOO(-)NH(4)(+) 是一个新的"结合辅助自导体".
- 通过TTF单元的质子化实现了自我兴奋剂.
- 结网在组装TTF部分和促进半导体行为的过程中起着至关重要的作用.
- 这项研究为设计具有可调节性质的有机导体提供了一个新的策略.
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