Mechanical single-molecule potentiometers with large switching factors from ortho-pentaphenylene foldamers

• Published in: Nature communications Vol. 12; no. 1; p. 167
• Main Authors: Li, Jinshi, Shen, Pingchuan, Zhen, Shijie, Tang, Chun, Ye, Yiling, Zhou, Dahai, Hong, Wenjing, Zhao, Zujin, Tang, Ben Zhong
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 08.01.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 147/138; 639/301/1005/1007; 639/301/357/339; 639/925/927/339; Anchoring; Charge transport; Chemistry; Conductance; Derivatives; Humanities and Social Sciences; Laboratories; Microscopy; multidisciplinary; Potentiometers; Resistance; Robustness; Scanning tunneling microscopy; Science; Science (multidisciplinary); Switching
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-20311-z

Molecular potentiometers that can indicate displacement-conductance relationship, and predict and control molecular conductance are of significant importance but rarely developed. Herein, single-molecule potentiometers are designed based on ortho -pentaphenylene. The ortho- pentaphenylene derivatives with anchoring groups adopt multiple folded conformers and undergo conformational interconversion in solutions. Solvent-sensitive multiple conductance originating from different conformers is recorded by scanning tunneling microscopy break junction technique. These pseudo-elastic folded molecules can be stretched and compressed by mechanical force along with a variable conductance by up to two orders of magnitude, providing an impressively higher switching factor (114) than the reported values (ca. 1~25). The multichannel conductance governed by through-space and through-bond conducting pathways is rationalized as the charge transport mechanism for the folded ortho -pentaphenylene derivatives. These findings shed light on exploring robust single-molecule potentiometers based on helical structures, and are conducive to fundamental understanding of charge transport in higher-order helical molecules. Molecular potentiometers that can indicate displacement-conductance relationship, and predict and control molecular conductance are of significant importance but rarely developed. Here, the authors design a robust single-molecule potentiometers based on helical structures and give insight in fundamental understanding of charge transport in higher-order helical molecules.