title: Single-Molecule Conductance of Viologen-Cucurbit[8]uril Host-Guest Complexes.
abstract: The local molecular environment is a critical factor which should be taken into account when measuring single-molecule electrical properties in condensed media or in the design of future molecular electronic or single molecule sensing devices. Supramolecular interactions can be used to control the local environment in molecular assemblies and have been used to create microenvironments, for instance, for chemical reactions. Here, we use supramolecular interactions to create microenvironments which influence the electrical conductance of single molecule wires. Cucurbit[8]uril (CB[8]) with a large hydrophobic cavity was used to host the viologen (bipyridinium) molecular wires forming a 1:1 supramolecular complex. Significant increases in the viologen wire single molecule conductances are observed when it is threaded into CB[8] due to large changes of the molecular microenvironment. The results were interpreted within the framework of a Marcus-type model for electron transfer as arising from a reduction in outer-sphere reorganization energy when the viologen is confined within the hydrophobic CB[8] cavity.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, CAS Center for Excellence in Nanoscience, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, China.|University of Chinese Academy of Sciences , Beijing 100049, China.|Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, CAS Center for Excellence in Nanoscience, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, China.
authors.forename: Shiyu
authors.initials: S
authors.lastname: Gan
authors.affiliation: Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
authors.forename: Andrea
authors.initials: A
authors.lastname: Vezzoli
authors.affiliation: Department of Chemistry, Durham University , South Road, Durham DH1 3LE, United Kingdom.
authors.forename: Ross J
authors.initials: RJ
authors.lastname: Davidson
authors.affiliation: Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
authors.forename: David C
authors.initials: DC
authors.lastname: Milan
authors.affiliation: Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
authors.forename: Konstantin V
authors.initials: KV
authors.lastname: Luzyanin
authors.affiliation: Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Higgins
authors.affiliation: Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Nichols
authors.affiliation: Department of Chemistry, Durham University , South Road, Durham DH1 3LE, United Kingdom.
authors.forename: Andrew
authors.initials: A
authors.lastname: Beeby
authors.affiliation: School of Chemistry and Biochemistry, University of Western Australia , 35 Stirling Highway, Perth, Western Australia 6009, Australia.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Low
authors.affiliation: Department of Chemistry, University of Liverpool , Crown Street, Liverpool L69 7ZD, United Kingdom.
authors.forename: Buyi
authors.initials: B
authors.lastname: Li
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, CAS Center for Excellence in Nanoscience, c/o Engineering Laboratory for Modern Analytical Techniques, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, China.
authors.forename: Li
authors.initials: L
authors.lastname: Niu
keywords: STM; cucurbituril; host−guest complexes; single molecule conductance; viologen