Isshiki Yuji, Montes Enrique, Nishino Tomoaki, Vázquez Héctor, Fujii Shintaro
Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 W4-10 Ookayama Meguro-ku Tokyo 152-8551 Japan
Institute of Physics, Czech Academy of Sciences Cukrovarnická 10 Prague CZ-162 00 Czech Republic
Chem Sci. 2024 Sep 23;15(42):17328-36. doi: 10.1039/d4sc05285d.
Designing and building single-molecule circuits with tailored functionalities requires a detailed knowledge of the junction electronic structure. The energy of frontier molecular orbitals and their electronic coupling with the electrodes play a key role in determining the conductance of nanoscale molecular circuits. Here, we developed a method for measuring the current-voltage (-) characteristics of single-molecule junctions with a time resolution that is two orders of magnitude higher than previously achieved. These - measurements with high temporal resolution, together with atomistic simulations, enabled us to characterize in detail the frontier molecular states and their evolution in sub-angstrom stretching of the junction. For a series of molecules, changes in the electronic structure were resolved as well as their fluctuations prior to junction breakdown. This study describes a new methodology to determine the key frontier MO parameters at single-molecule junctions and demonstrates how these can be mechanically tuned at the single-molecule level.
设计和构建具有定制功能的单分子电路需要对结的电子结构有详细了解。前沿分子轨道的能量及其与电极的电子耦合在确定纳米级分子电路的电导方面起着关键作用。在此，我们开发了一种方法来测量单分子结的电流-电压（I-V）特性，其时间分辨率比以前提高了两个数量级。这些具有高时间分辨率的I-V测量，结合原子模拟，使我们能够详细表征前沿分子态及其在结的亚埃拉伸中的演化。对于一系列分子，不仅解析了电子结构的变化，还解析了结击穿前的波动。本研究描述了一种确定单分子结关键前沿分子轨道参数的新方法，并展示了如何在单分子水平上对其进行机械调谐。
