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Updated: Jul 4, 2025
08:43
Effect of Bending on the Electrical Characteristics of Flexible Organic Single Crystal-based Field-effect Transistors
Published on: November 7, 2016
8.1K
Influence of Peripheral Alkyl Groups on Junction Configurations in Single-Molecule Electronics
Luca Ornago1, Patrick Zwick2, Sebastiaan van der Poel1
1Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
The Journal of Physical Chemistry. C, Nanomaterials and Interfaces
|January 31, 2024
Summary
Adding alkyl side chains to molecules can alter their behavior in single-molecule junctions. While intended to reduce molecular interactions, these chains can create new configurations, broadening conductance peaks and requiring careful design for molecular electronics applications.
Area of Science:
- Molecular electronics
- Supramolecular chemistry
- Nanotechnology
Background:
- Lateral alkyl chains are used to reduce molecular aggregation in solution.
- Minimizing backbone interactions is key in molecular assembly.
Purpose of the Study:
- To investigate if alkyl chains influence configurations in single-molecule junctions.
- To understand the effect of bulky groups on molecular junction properties.
Main Methods:
- Mechanically controllable break junction (MCBJ) measurements.
- Clustering-based data analysis.
- Utilizing model compounds with varied alkyl side chains.
Main Results:
- Alkyl side chains promote electrode-molecule configurations not seen without them.
- A broadening of the conductance peak in one-dimensional histograms was observed.
- The presence of alkyl chains influences the stability and geometry of molecular junctions.
Conclusions:
- The strategy of using alkyl chains to control molecular interactions generalizes to single-molecule junctions.
- Careful design is needed to balance solubility benefits with potential changes in junction configurations.
- Optimization is crucial for tailoring molecular electronics components with alkylated aromatic compounds.
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