A cellular automation model for the catalytic CO+O-2 surface reaction is in
troduced by means of building oriented two-pointed "suprastructure" in latt
ice. Reactions can only occur in the suprastructures. We use reaction proba
bility as variable to control reactions in suprastructures, The reactions s
ystem exhibits three phases; the GO-poisoned, the O-poisoned and the reacti
ve phase, in consistence with the Monte-Carlo results.