Side-Group-Mediated Mechanical Conductance Switching in Molecular Junctions
Side-Group-Mediated Mechanical Conductance Switching in Molecular Junctions
复制标题
DOI：
10.1002/anie.201709419
复制
发表时间：
2017-11-27
影响因子：
16.6
通讯作者：
Higgins, Simon J.
中科院分区：
文献类型：
--
作者：
Ismael, Ali Khalid;Wang, Kun;Higgins, Simon J.
分子电子学中的一个关键目标是具有可切换电特性的分子。两种电状态之间的切换已被证明使用这样的刺激，如光，电化学电压，络合和机械调制。后者的一个经典例子是4，4-联吡啶的切换，导致约1个数量级的电导调制。在这里，我们描述了使用侧基化学来控制单分子机电开关的性质，该开关可以通过重复的压缩和伸长在两个导电状态之间循环。虽然大的烷基取代基抑制开关行为，共轭侧基恢复它。DFT计算表明，芳基部分和金属电极之间的弱相互作用是负责所观察到的现象。这是一个显着的扩展单分子电子学工具箱的设计与机电性能的结。
A key target in molecular electronics has been molecules having switchable electrical properties. Switching between two electrical states has been demonstrated using such stimuli as light, electrochemical voltage, complexation and mechanical modulation. A classic example of the latter is the switching of 4,4-bipyridine, leading to conductance modulation of around 1 order of magnitude. Here, we describe the use of side-group chemistry to control the properties of a single-molecule electromechanical switch, which can be cycled between two conductance states by repeated compression and elongation. While bulky alkyl substituents inhibit the switching behavior, -conjugated side-groups reinstate it. DFT calculations show that weak interactions between aryl moieties and the metallic electrodes are responsible for the observed phenomenon. This represents a significant expansion of the single-molecule electronics tool-box for the design of junctions with electromechanical properties.