title: Do molecular conductances correlate with electrochemical rate constants? Experimental insights.
abstract: We measured single-molecule conductances for three different redox systems self-assembled onto gold by the STMBJ method and compared them with electrochemical heterogeneous rate constants determined by ultrafast voltammetry. It was observed that fast systems indeed give higher conductance. Monotonous dependency of conductance on potential reveals that large molecular fluctuations prevent the molecular redox levels to lie in between the Fermi levels of the electrodes in the nanogap configuration. Electronic coupling factors for both experimental approaches were therefore evaluated based on the superexchange mechanism theory. The results suggest that coupling is surprisingly on the same order of magnitude or even larger in conductance measurements whereas electron transfer occurs on larger distances than in transient electrochemistry.
authors.affiliation: Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, China.
authors.forename: Xiao-Shun
authors.initials: XS
authors.lastname: Zhou
authors.forename: Ling
authors.initials: L
authors.lastname: Liu
authors.forename: Philippe
authors.initials: P
authors.lastname: Fortgang
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Lefevre
authors.forename: Anna
authors.initials: A
authors.lastname: Serra-Muns
authors.forename: Noureddine
authors.initials: N
authors.lastname: Raouafi
authors.forename: Christian
authors.initials: C
authors.lastname: Amatore
authors.forename: Bing-Wei
authors.initials: BW
authors.lastname: Mao
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Maisonhaute
authors.forename: Bernd
authors.initials: B
authors.lastname: Schöllhorn