美国伊利诺伊大学厄巴纳-香槟分校Schroeder, Charles M.团队，报道了形状持久的阶梯分子在单分子结中表现出与纳米间隙无关的电导。相关研究成果发表在2024年8月26日出版的国际学术期刊《自然—化学》。

分子电子设备需要精确控制单分子中的电流。然而，单分子的电子输运性质在很大程度上取决于纳米结中的动态分子构象。

该文中，研究人员报告了一种使用形状持久性分子控制分子电导的独特策略。通过一锅多组分梯化策略合成的化学多样的带电梯状分子，显示出几乎与结位移无关的分子电导（d[log（G/G0）]/dx≈-0.1nm^-1），这与非梯状类似物观察到的纳米间隙依赖电导（d[mog（G/G0）]/dz≈-7nm^-1）形成鲜明对比。

梯形分子在动态结位移过程中显示出异常窄的分子电导分布，这归因于形状持久的骨架和末端锚基团的受限旋转。这些原理进一步扩展到蝴蝶状分子，从而证明了该策略实现间隙无关电导的通用性。

总的来说，研究工作为使用形状持久性分子控制分子电导提供了重要途径。

附：英文原文

Title: Shape-persistent ladder molecules exhibit nanogap-independent conductance in single-molecule junctions

Author: Liu, Xiaolin, Yang, Hao, Harb, Hassan, Samajdar, Rajarshi, Woods, Toby J., Lin, Oliver, Chen, Qian, Romo, Adolfo I. B., Rodrguez-Lpez, Joaqun, Assary, Rajeev S., Moore, Jeffrey S., Schroeder, Charles M.

Issue&Volume: 2024-08-26

Abstract: Molecular electronic devices require precise control over the flow of current in single molecules. However, the electron transport properties of single molecules critically depend on dynamic molecular conformations in nanoscale junctions. Here we report a unique strategy for controlling molecular conductance using shape-persistent molecules. Chemically diverse, charged ladder molecules, synthesized via a one-pot multicomponent ladderization strategy, show a molecular conductance (d[log(G/G0)]/dx≈0.1nm1) that is nearly independent of junction displacement, in stark contrast to the nanogap-dependent conductance (d[log(G/G0)]/dx≈7nm1) observed for non-ladder analogues. Ladder molecules show an unusually narrow distribution of molecular conductance during dynamic junction displacement, which is attributed to the shape-persistent backbone and restricted rotation of terminal anchor groups. These principles are further extended to a butterfly-like molecule, thereby demonstrating the strategy’s generality for achieving gap-independent conductance. Overall, our work provides important avenues for controlling molecular conductance using shape-persistent molecules.

DOI: 10.1038/s41557-024-01619-5

Source: https://www.nature.com/articles/s41557-024-01619-5