Turning the Tap: Conformational Control of Quantum Interference to Modulate Single Molecule Conductance

Jiang, Feng; Trupp, Douglas; Algethami, Norah; Zheng, Haining; He, Wenxiang; Alqorashi, Afaf; Zhu, Chenxu; Tang, Chun; Li, Ruihao; Liu, Junyang; Sadeghi, Hatef; Shi, Jia; Davidson, Ross; Korb, Marcus; Naher, Masnun; Sobolev, Alexandre N.; Sangtarash, Sara; Low, Paul J.; Hong, Wenjing; Lambert, Colin

Abstract

Together with the more intuitive and commonly recognized conductance mechanisms of charge‐hopping and tunneling, quantum interference (QI) phenomena have been identified as important factors affecting charge transport through molecules. Consequently, establishing simple, flexible molecular design strategies to understand, control and exploit QI in molecular junctions poses an exciting challenge. Here we demonstrate that destructive quantum interference (DQI) in meta‐substituted phenylene ethylene‐type oligomers (m‐OPE) can be tuned by changing the position and conformation of pendant methoxy (OMe) substituents around the central phenylene ring. These substituents play the role of molecular‐scale ‘taps’, which can be switched on or off to control the current flow through a molecule. Our experimental results conclusively verify recently postulated magic ratio and orbital product rules, and highlight a novel chemical design strategy for tuning and gating DQI features, to create single‐molecule devices with desirable electronic functions.

Citation

Jiang, F., Trupp, D., Algethami, N., Zheng, H., He, W., Alqorashi, A., …Lambert, C. (2019). Turning the Tap: Conformational Control of Quantum Interference to Modulate Single Molecule Conductance. Angewandte Chemie, 58(52), 18987-18993. https://doi.org/10.1002/anie.201909461

• Journal Article Type: Article
• Acceptance Date: Oct 14, 2019
• Online Publication Date: Oct 31, 2019
• Publication Date: Dec 19, 2019
• Deposit Date: Oct 17, 2019
• Publicly Available Date: Oct 31, 2020
• Journal: Angewandte Chemie
• Print ISSN: 0044-8249
• Electronic ISSN: 1521-3757
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 58
• Issue: 52
• Pages: 18987-18993
• DOI: https://doi.org/10.1002/anie.201909461