Campus Units

Physics and Astronomy, Mathematics, Ames Laboratory

Document Type

Article

Publication Version

Published Version

Publication Date

1990

Journal or Book Title

The Journal of Chemical Physics

Volume

93

Issue

11

First Page

8397

Last Page

8398

DOI

10.1063/1.459273

Abstract

Irreversible adsorption of diatomics on crystalline surfaces is sometimes modeled as random dimer filling of adjacent pairs of sites on a lattice. We note that this process can be implemented in two distinct ways: (i) randomly pick adjacent pairs of sites,  jj’, and fill  jj’ only if both are empty (horizontal transition state); or (ii) randomly pick a single site,  j, and if  j and at least one neighbor are empty, then fill  j and a randomly chosen empty neighbor (vertical transition state). Here it is instructive to consider processes which also include competitive random monomer filling of single sites. We find that although saturation (partial) coverages differ little between the models for pure dimer filling, there is a significant difference for comparable monomer and dimer filling rates. We present exact results for saturation coverage behavior for a linear lattice, and estimates for a square lattice. Ramifications for simple models of CO oxidation on surfaces are indicated.

Comments

This article is published as Nord, R. S., and J. W. Evans. "Inequivalent models of irreversible dimer filling:‘‘Transition state’’dependence." The Journal of chemical physics 93, no. 11 (1990): 8397-8398, doi:10.1063/1.459273. Posted with permission.

Copyright Owner

American Institute of Physics

Language

en

File Format

application/pdf

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