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Stokes formula and density perturbances for driven tracer diffusion in an adsorbed monolayer
Benichou1, Cazabat, De Coninck J
1Laboratoire de Physique Theorique des Liquides (CNRS-UMR 7600), Universite Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, France.
Physical Review Letters
|October 4, 2000
Summary
We investigated the friction of 2D adsorbed molecules. Under small forces, their motion resembles viscous flow, leading to a 2D Stokes
Area of Science:
- Surface Science
- Physical Chemistry
- Statistical Mechanics
Background:
- Understanding friction at the nanoscale is crucial for material properties.
- Adsorbed monolayers exhibit unique behaviors distinct from bulk materials.
Purpose of the Study:
- To investigate the intrinsic friction of two-dimensional (2D) adsorbed monolayers.
- To model the resistance experienced by a tracer molecule within these monolayers.
Main Methods:
- Utilized the Langmuir model for delocalized adsorption.
- Calculated resistance using a tracer molecule driven by an external force.
- Derived a 2D analog of Stokes' formula.
Main Results:
- Observed viscous-like behavior for the tracer under small driving forces.
- Determined the friction coefficient for 2D adsorbates.
- Characterized the stationary particle distribution around the driven impurity.
Conclusions:
- The study provides a framework for understanding nanoscale friction in 2D systems.
- The derived Stokes' analog is applicable to mobile adsorbates on solid surfaces.
- Results offer insights into the dynamics of driven impurities in monolayers.
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