title: Length-dependent conductance of conjugated molecular wires synthesized by stepwise "click" chemistry.
abstract: We report the preparation and electrical characterization of conjugated oligophenylenetriazole (OPT) wires having systematically varied lengths up to 10 nm. OPT wires were built from gold substrates using Cu(I)-catalyzed azide alkyne cycloaddition and characterized comprehensively by RAIRS, ellipsometry, and XPS. We observed a clear transition in direct current (DC) transport from tunneling to hopping in a length range between 4 and 5 nm as previously established for oligoarylimine wires. Stepwise click cycloaddition represents a new efficient method to prepare long conjugated molecular wire self-assembled monolayers (SAMs) on Au surfaces for conduction measurements and is expected to be compatible with a variety of functionalities and bonding architectures in the wire backbones.
authors.affiliation: Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Luo
authors.forename: C Daniel
authors.initials: CD
authors.lastname: Frisbie