The monomer-dimer model of heterogeneous catalysis with a finite reaction rate

Abstract

The authors study the Ziff-Gulari-Barshad (1986) monomer-dimer model for catalysis with finite reaction and adsorption rates. A recent paper shows numerical evidence for the existence of a tricritical point at a reaction probability value rc approximately=0.14, below which there is no steady state reactive phase, but its ad hoc mean-field approach fails to reproduce this result. The authors' numerical simulations on significantly bigger lattices and using the more sensitive technique of constant coverage, show the absence of a tricritical point even for r as small as 0.01. They also conduct a mean-field analysis based on Dickman's cluster approximation (1986), a self-contained method which does not require external parameters. It too supports their claim that there is no tricritical point in the monomer-dimer model with finite reaction rate.