Structure‐Independent Conductance of Thiophene‐Based Single‐Stacking Junctions. Issue 8 (16th January 2020)

• Record Type: Journal Article
• Authors: Li, Xiaohui; Wu, Qingqing; Bai, Jie; Hou, Songjun; Jiang, Wenlin; Tang, Chun; Song, Hang; Huang, Xiaojuan; Zheng, Jueting; Yang, Yang; Liu, Junyang; Hu, Yong; Shi, Jia; Liu, Zitong; Lambert, Colin J.; Zhang, Deqing; Hong, Wenjing
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 8(2020)
• Page Start: 3280
• Page End: 3286
• Publication Date: 2020-01-16
• Subjects: conducting materials -- conjugation -- mechanically controllable break junctions -- intermolecular charge transport -- thiophene junctions; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201913344
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The experimental investigation of intermolecular charge transport in π‐conjugated materials is challenging. Herein, we describe the investigation of charge transport through intermolecular and intramolecular paths in single‐molecule and single‐stacking thiophene junctions by the mechanically controllable break junction (MCBJ) technique. We found that the ability for intermolecular charge transport through different single‐stacking junctions was approximately independent of the molecular structure, which contrasts with the strong length dependence of conductance in single‐molecule junctions with the same building blocks, and the dominant charge‐transport path of molecules with two anchors transited from an intramolecular to an intermolecular path when the degree of conjugation increased. An increase in conjugation further led to higher binding probability owing to the variation in binding energies, as supported by DFT calculations. Abstract : Which mode of transport? The conductance of thiophene‐based single‐stacking junctions was found to be nearly independent of the conjugation pattern of the molecular structure. When the length of the conjugated region increased, there was a change in the dominant charge‐transport path from intramolecular to intermolecular (see picture).