Ziff-Gulari-Barshad Model in Zacros

The conceptual CO oxidation model by Ziff, Gulari and Barshad (ZGB) served as the first demonstration of kinetic phase transitions in heterogeneous catalytic systems.¹ The model includes 3 irreversible events: non-dissociative adsorption of CO, dissociative adsorption of O₂, and fast reaction between an O adatom and a CO adsorbate. Such a model can be easily set up in Zacros. In this tutorial we will discuss how to create the input files for such a simulation. By changing the molar fractions of the CO and O₂ species, one can reproduce the phase diagram of the original paper by Ziff et al.¹