Random Sequential Adsorption Model for the Differential Coverage of Gold (111) Surfaces by Two Related Silicon Phthalocyanines

Abstract

We present a simple model for the discrepancy in the coverage of a gold (111) surface by two silicon phthalocyanines. The model involves random sequential adsorption (RSA) simulations with two different landing molecules, one of which is tilted relative to the substrate surface and can (under certain conditions) allow neighboring molecules to overlap. This results in a jamming limit that is near full coverage of the surface. The nonoverlapping molecules reproduce the half-monolayer jamming limit that is common in continuum RSA models with ellipsoidal landers. Additionally, the overlapping molecules exhibit orientational correlation and orientational domain formation evolving out of a purely random adsorption process.

XPS and SERS Study of Silicon Phthalocyanine Monolayers: Umbrella vs Octopus Design Strategies for Formation of Oriented SAMs

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Ganglioside Microarrays for Toxin Detection

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Design of acoustic wave biochemical sensors using micro-electro-mechanical systems

“…Thus, it is necessary to determine if the error will lie within acceptable limits when such masses are bound. We assume random sequential absorption coverage of the binding regions, 55,56 and calculate the number of antibodies bound if we model the antibody as a sphere, and assume a "footprint" of ͑6.2 nm͒ 2 . The effect of the increased hydrodynamic radius is counteracted by the reduced number of molecules capable of binding to the membrane surface, so this case is covered by the work shown in Fig.…”