Related Experiment Video
Updated: May 29, 2026

Studying DNA Looping by Single-Molecule FRET
Published on: June 28, 2014
Length-dependent conductance of conjugated molecular wires synthesized by stepwise "click" chemistry
1Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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.
Related Concept Videos
Molecular Weight of Step-Growth Polymers
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
Electrical Conductivity
In a practical conductor, an applied electric field may be sustained, causing a flow of electrons, which produce a current. The differential form of the current, the current density, is related to the electric field.
More generally, it is related to the force per unit charge, which involves the...
Electrical Transport
Kohlraush’s Law and its Applications
Debye–Huckel–Onsager Conductance Equation

