Home > Research > Publications & Outputs > Quasi-Free Electron States Responsible for Sing...

Electronic data

  • Manuscript

    Accepted author manuscript, 1.56 MB, PDF document

    Available under license: CC BY: Creative Commons Attribution 4.0 International License


Text available via DOI:

View graph of relations

Quasi-Free Electron States Responsible for Single-Molecule Conductance Enhancement in Stable Radical

Research output: Contribution to Journal/MagazineJournal articlepeer-review

<mark>Journal publication date</mark>4/05/2023
<mark>Journal</mark>The Journal of Physical Chemistry Letters
Issue number17
Number of pages7
Pages (from-to)4004-4010
Publication StatusPublished
Early online date21/04/23
<mark>Original language</mark>English


Stable organic radicals, which possess half-filled orbitals in the vicinity of the Fermi energy, are promising candidates for electronic devices. In this Letter, using a combination of scanning-tunneling-microscopy-based break junction (STM-BJ) experiments and quantum transport theory, a stable fluorene-based radical is investigated. We demonstrate that the transport properties of a series of fluorene derivatives can be tuned by controlling the degree of localization of certain orbitals. More specifically, radical has a delocalized half-filled orbital resulting in Breit-Wigner resonances, leading to an unprecedented conductance enhancement of 2 orders of magnitude larger than the neutral nonradical counterpart ( ). In other words, conversion from a closed-shell fluorene derivative to the free radical in opens an electron transport path which massively enhances the conductance. This new understanding of the role of radicals in single-molecule junctions opens up a novel design strategy for single-molecule-based spintronic devices.