Related Experiment Video
Updated: Jun 25, 2025
09:43
Study of Short Peptide Adsorption on Solution Dispersed Inorganic Nanoparticles Using Depletion Method
Published on: April 11, 2020
6.6K
Abortive reaction leads to selective adsorbate rotation
Yi-Fang Lai1, Lydie Leung1, Matthew J Timm2
1Lash Miller Chemical Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada. john.polanyi@utoronto.ca.
Faraday Discussions
|May 29, 2024
Summary
Electron-induced fluorine atoms from CF3 adsorbates act as projectiles, causing rotational excitation in allyl molecules. This collision leads to an abortive chemical reaction and allyl isomerization on a copper surface.
Area of Science:
- Surface Science
- Physical Chemistry
- Nanotechnology
Background:
- Electron-induced dissociation of adsorbates is a key process in surface chemistry.
- Understanding molecule-surface interactions is crucial for designing nanoscale chemical processes.
- Fluorocarbon adsorbates offer unique reactivity pathways on metal surfaces.
Purpose of the Study:
- To investigate the dynamics of electron-induced dissociation of CF3 on Cu(110).
- To study the collision outcomes between energetic F-atom projectiles and co-adsorbed allyl molecules.
- To elucidate the mechanism of allyl excitation and subsequent chemical reactions.
Main Methods:
- Scanning Tunneling Microscopy (STM) at 4.6 K to observe dissociation and collisions.
- Molecular Dynamics (MD) simulations to model the collisional dynamics.
- Utilizing directed energetic F-atom 'projectiles' generated from CF3 dissociation.
Main Results:
- Directed, energetic F-atom projectiles were formed from CF3 dissociation on Cu(110).
- Collisions induced rotational excitation (clockwise/anti-clockwise) in target allyl molecules.
- MD simulations linked excitation to an abortive reaction, stretching H-C bonds and facilitating allyl isomerization.
Conclusions:
- Electron-induced dissociation can create directed reactive species for surface chemistry.
- Collision geometry dictates the rotational excitation of target molecules.
- This study reveals a novel pathway for inducing surface reactions and isomerization via energetic atom projectiles.
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