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Critical behavior of repulsively interacting particles adsorbed on disordered triangular lattices
M A Perarnau1, P M Centres, F Bulnes
1Departamento de Física, Instituto de Física Aplicada, Universidad Nacional de San Luis-CONICET, Chacabuco 917, D5700BWS San Luis, Argentina.
Physical Chemistry Chemical Physics : PCCP
|September 10, 2010
Summary
This study models amorphous solids using a disordered triangular lattice to investigate monomer adsorption. Introducing surface defects significantly alters adsorption thermodynamics compared to regular lattices.
Area of Science:
- Surface Science
- Computational Physics
- Materials Science
Background:
- Amorphous solids possess unique surface properties due to defects.
- Understanding adsorption on disordered surfaces is crucial for materials applications.
Purpose of the Study:
- To investigate how surface disorder affects monomer adsorption thermodynamics.
- To model amorphous solids using a tunable triangular lattice with attenuated bonds.
Main Methods:
- Grand canonical Monte Carlo simulations were employed.
- A triangular lattice model with randomly distributed attenuated bonds was used.
- Adsorption isotherms and differential heats of adsorption were calculated.
Main Results:
- Surface disorder, controlled by bond fraction (ρ) and attenuation factor (r), significantly modifies adsorption.
- Behavior ranges from bond-diluted (r=0) to regular lattices (r=1).
- The order-disorder phase transition persists but is altered by disorder.
Conclusions:
- Surface defects introduce rich and tunable adsorption behaviors.
- The model provides insights into the thermodynamics of adsorption on amorphous surfaces.
- Phase transition criticality is dependent on disorder parameters and temperature.
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