Year: 1996
Type: article
Abstract: We study the diffusion and submonolayer spreading of chainlike molecules on surfaces. Using the fluctuating bond model, we extract the collective and tracer diffusion coefficients ${D}_{c}$ and ${D}_{t}$ with a variety of methods. We show that ${D}_{c}(\ensuremath{\theta})$ has unusual behavior as a function of the coverage $\ensuremath{\theta}$. It first increases, but after a maximum goes to zero as $\ensuremath{\theta}\ensuremath{\rightarrow}1$. We show that the increase is due to entropic repulsion that leads to steep density profiles for spreading droplets seen in experiments. We also develop an analytic model for ${D}_{c}(\ensuremath{\theta})$ which agrees well with the simulations.
Source: Physical Review Letters
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2963786014