title: Conductance of a single flexible molecular wire composed of alternating donor and acceptor units.
abstract: Molecular-scale electronics is mainly concerned by understanding charge transport through individual molecules. A key issue here is the charge transport capability through a single--typically linear--molecule, characterized by the current decay with increasing length. To improve the conductance of individual polymers, molecular design often either involves the use of rigid ribbon/ladder-type structures, thereby sacrificing for flexibility of the molecular wire, or a zero band gap, typically associated with chemical instability. Here we show that a conjugated polymer composed of alternating donor and acceptor repeat units, synthesized directly by an on-surface polymerization, exhibits a very high conductance while maintaining both its flexible structure and a finite band gap. Importantly, electronic delocalization along the wire does not seem to be necessary as proven by spatial mapping of the electronic states along individual molecular wires. Our approach should facilitate the realization of flexible 'soft' molecular-scale circuitry, for example, on bendable substrates.
authors.affiliation: 1] Department of Physical Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, Berlin 14195, Germany.. [2] Department of Physical Chemistry, University of Graz, Graz 8010, Austria.
authors.forename: Christophe
authors.initials: C
authors.lastname: Nacci
authors.affiliation: Institute of Materials Research and Engineering (IMRE), Singapore 117602, Singapore.
authors.forename: Francisco
authors.initials: F
authors.lastname: Ample
authors.affiliation: Department of Chemistry and IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin 12489, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Bleger
authors.affiliation: Department of Chemistry and IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin 12489, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Hecht
authors.affiliation: 1] Nanosciences Group and MANA Satellite, CEMES-CNRS, Toulouse 31055, France. [2] International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Christian
authors.initials: C
authors.lastname: Joachim
authors.affiliation: 1] Department of Physical Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, Berlin 14195, Germany.. [2] Department of Physical Chemistry, University of Graz, Graz 8010, Austria.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Grill