测量单个结合分子的导电性
Tali Dadosh1, Yoav Gordin, Roman Krahne
1Department of Condensed Matter Physics, Weizmann Institute of Science, 76100 Rehovot, Israel.
Nature
|August 5, 2005
概括
研究人员通过创建金纳米粒子二极管来研究单个分子中的电导. 与完全结合的系统相比,结合分子中的定位组显著抑制电导.
科学领域:
- 分子电子学分子电子学
- 有机电子学有机电子学
- 纳米技术纳米技术
背景情况:
- 分子中的电导依赖于非局部化的电子轨道和强的硫金属键.
- 化结合有机分子对分子导体有前途,但对单分子装置需要先进的技术.
- 分子的大小 (~1 nm) 对于创建功能单分子电子设备提出了挑战.
研究的目的:
- 开发一种用于接触和研究单个分子的创新方法.
- 为了研究结合分子内的局部电子群对电导的影响.
- 为了比较完全结合的分子的导电性与含有结合破坏元素的分子.
主要方法:
- 合成了由两种金纳米颗粒组成的二元结构,由二氧化有机分子连接在一起.
- 采用静电陷来将二极管放置在两个金属电极之间,用于单分子测量.
- 测试了三种分子:4,4'-二乙烯基乙醇 (BPD),二-4-甲乙烯 (BPE) 和1,4-二甲乙醇 (BDMT).
主要成果:
- 通过使用金纳米粒子二极管方法,成功与单个分子建立了电接触.
- 与完全结合的BPD相比,在中断结合的分子 (BPE和BDMT) 中观察到显著抑制的电导.
- 证明氧和甲基组有效地定位电子轨道,阻碍导电.
结论:
- 黄金纳米粒子二极管方法使可靠的单分子电气测量成为可能.
- 在有机分子中,即使是单个原子或群体的结合分解,也会大大降低电导率.
- 轨道移位对于分子导体中有效的电荷传输至关重要.
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