%0 Journal Article
%A Li, Z.
%A Pobelov, I.
%A Han, B.
%A Wandlowski, Th.
%A Blaszcyk, A.
%A Mayor, M.
%T Conductance of redox-active single molecular junctions: an electrochemical approach
%J Nanotechnology
%V 18
%@ 0957-4484
%C Bristol
%I IOP Publ.
%M PreJuSER-53215
%P 044018
%D 2007
%Z Record converted from VDB: 12.11.2012
%X The conductance of molecular junctions formed of N, N'-bis(n-thioalkyl)4,4'-bipyridinium bromides or alkanedithiols between a gold (Au) scanning tunnelling microscope tip and a Au(111)-(1x1) electrode has been studied at electrified solid/liquid interfaces. A statistical analysis based on large sets of individual current - distance traces was applied to obtain the electrical conductance of single junctions. The one-electron reduction of the viologen moiety from the dication V2+ to the radical cation state V+. gives rise to a 50% increase of the junction conductance. Increasing the length of the alkyl spacer units leads to a tunnelling decay constant ss(CH2) = 5.9-6.1 nm(-1). This value is significantly lower than ss(CH2) = 8.2 nm(-1) estimated for molecular junctions of alkanedithiols. The difference is attributed to conformational changes within the two junctions. The contact conductance was estimated to 10 mu S.
%K J (WoSType)
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000243841000019
%R 10.1088/0957-4484/18/4/044018
%U https://juser.fz-juelich.de/record/53215