Substitution Pattern Controlled Quantum Interference in [2.2]Paracyclophane-Based Single-Molecule Junctions

Substitution Pattern Controlled Quantum Interference in [2.2]Paracyclophane-Based Single-Molecule Junctions

Reznikova, Ksenia (University of Basel)
Hsu, C. (TU Delft QN/van der Zant Lab; Kavli institute of nanoscience Delft)
Schosser, Werner M. (Universität Augsburg)
Gallego, Almudena (University of Basel)
Beltako, Katawoura (Universität Augsburg)
Pauly, Fabian (Universität Augsburg)
van der Zant, H.S.J. (TU Delft QN/van der Zant Lab; Kavli institute of nanoscience Delft)
Mayor, Marcel (University of Basel; Karlsruhe Institut für Technologie; Sun Yat-sen University)

2021

Quantum interference (QI) of electron waves passing through a single-molecule junction provides a powerful means to influence its electrical properties. Here, we investigate the correlation between substitution pattern, conductance, and mechanosensitivity in [2.2]paracyclophane (PCP)-based molecular wires in a mechanically controlled break junction experiment. The effect of the meta versus para connectivity in both the central PCP core and the phenyl ring connecting the terminal anchoring group is studied. We find that the meta-phenyl-anchored PCP yields such low conductance levels that molecular features cannot be resolved; in the case of para-phenyl-coupled anchoring, however, large variations in conductance values for modulations of the electrode separation occur for the pseudo-para-coupled PCP core, while this mechanosensitivity is absent for the pseudo-meta-PCP core. The experimental findings are interpreted in terms of QI effects between molecular frontier orbitals by theoretical calculations based on density functional theory and the Landauer formalism.

http://resolver.tudelft.nl/uuid:f65ef775-b9a1-4a49-a15e-51942d2b8cb8

https://doi.org/10.1021/jacs.1c06966

0002-7863

Journal of the American Chemical Society, 143 (34), 13944-13951

Institutional Repository

journal article

© 2021 Ksenia Reznikova, C. Hsu, Werner M. Schosser, Almudena Gallego, Katawoura Beltako, Fabian Pauly, H.S.J. van der Zant, Marcel Mayor