Ziff–Gulari–Barshad model. Classical microkinetic model of catalytic oxidation of carbon monoxide to carbon dioxide. See https://doi.org/10.1103/PhysRevLett.56.2553 for details. This simulation has been conducted with the latest version of SuSMoST ( http://susmost.com/ ). Here y_CO = 0.535 that is just 0.01 larger than the critical value of transition to carbon monoxide poisoning y_CO = 0.525. Red spheres are adsorbed oxygen atoms, gray spheres - adsorbed CO molecules.