奥利古提芬的长度依赖导电性
Brian Capozzi1, Emma J Dell, Timothy C Berkelbach
1Department of Applied Physics and Mathematics, Columbia University , New York, New York 10027, United States.
Journal of the American Chemical Society
|July 9, 2014
概括
单分子导电性测量显示了异常行为,导电性不会随长度呈指数衰减. 连接处的分子构造可能解释了这种意想不到的趋势.
科学领域:
- 分子电子学分子电子学
- 凝聚物质物理学 凝聚物质物理学
- 有机化学 有机化学
背景情况:
- 奥利戈提奥芬是分子电子学的有希望的有机半导体.
- 了解单个分子中的电荷传输对于设备小型化至关重要.
- 扫描道显微镜 (STM) 断路技术使单分子导电性测量成为可能.
研究的目的:
- 测量和分析不同长度的寡二的单分子导电性.
- 为了研究分子结构和电荷传输特性之间的关系.
- 了解影响单分子连接处导电性的因素.
主要方法:
- 使用基于显微镜的扫描道断路结合 (STM-BJ) 技术.
- 用甲基硫化物链接剂合成和特征化了寡二烯 (1-6个二烯单位).
- 采用光学光谱学和电化学探测电子性质.
主要成果:
- 观察到寡基的异常导电性行为;导电性峰值没有显示明显的指数式衰变随着链条长度的增加.
- 电子特性与导电量测量相关.
- 识别了分子结点内的潜在形状变化.
结论:
- 观察到的异常导电趋势表明,超出简单链条长度的因素影响了电荷传输.
- 扫描道显微镜中分子构造的断裂结是影响单分子导电性的关键因素.
- 需要进行进一步的研究,以充分阐明构造在基于寡甲的分子电子学中的作用.
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