Reversible 1D chain-reaction gives rise to an atomic-scale Newton's cradle

Area of Science:

• Surface science
• Chemical physics
• Materials science

Background:

• Fluorocarbon adsorbates on metal surfaces are relevant for materials science.
• Understanding atom-surface interactions is crucial for catalysis and nanotechnology.

Purpose of the Study:

• To investigate the dynamics of energy transfer in atom-surface interactions.
• To observe the propagation of kinetic energy along a one-dimensional molecular chain.

Main Methods:

• Utilized scanning tunneling microscopy (STM) to observe atomic-scale events.
• Experimentally directed a fluorine atom with controlled translational energy (∼1 eV) towards fluorocarbon adsorbates on a Copper(110) surface.

Main Results:

• Observed sequential 'knock-on' reactions propagating along the one-dimensional fluorocarbon chain.
• Documented hot fluorine atoms traveling back and forth along the line in multiple cycles.
• The observed motion was analogous to the rocking of a macroscopic Newton's cradle.

Conclusions:

• Demonstrated a novel mechanism for energy transfer and reaction propagation along a 1D molecular system.
• Highlighted the potential for controlled, chain-like reactions on surfaces.
• Provided a visual and mechanistic model for energy dissipation in low-dimensional systems.