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Electrical Catalysis of Forbidden Transitions in Single-Molecule Devices
Ruihao Li1, Ran Liu1, Shima Ghasemi2
1Biodesign Center for Bioelectronics and Biosensors at Arizona State University, Tempe, AZ, 85287, USA.
Advanced Materials (Deerfield Beach, Fla.)
|December 12, 2025
Summary
Researchers electrically catalyzed forbidden chemical reactions using a nanoscale junction. By manipulating a molecule
Area of Science:
- Physical Chemistry
- Chemical Physics
- Molecular Engineering
Background:
- Molecular orbital symmetry governs chemical reaction pathways.
- Reactions violating symmetry conservation face high energy barriers, deemed 'forbidden'.
- Photochemical methods are traditionally required for symmetry-forbidden reactions.
Purpose of the Study:
- To demonstrate electrical catalysis of symmetry-forbidden reactions.
- To investigate inducing cycloaddition in a norbornadiene (NBD) derivative.
- To explore the role of nanoconfinement and voltage in overcoming reaction barriers.
Main Methods:
- Utilizing a single molecule bound between two electrodes in a nanoscale junction.
- Applying a small voltage to the molecular junction.
- Employing single-molecule Raman spectroscopy for in situ reaction dynamics tracking.
- Sterically maneuvering the molecule into a configuration near the transition state.
Main Results:
- Successfully induced a forbidden cycloaddition reaction (NBD to QC) using electrical catalysis.
- Showed that nanoconfinement and precise molecular positioning are crucial.
- Demonstrated that electrical catalysis can overcome traditional orbital symmetry selection rules.
Conclusions:
- Electrical catalysis is a viable method for inducing symmetry-forbidden reactions.
- Nanoscale junctions offer a platform for controlling and driving challenging chemical transformations.
- Precise steric control and applied voltage can bypass photochemical requirements for certain reactions.
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