A simple model for two competing chemical reactions

We study a competitive reaction model in one dimension with different reactivity weights for the reactions. We consider the A + A → A2 auto-catalytic reaction model and the A + B → AB monomer-monomer reaction model, where A and B are monomers arriving at the surface with probabilities yA and yB, respectively. The model is studied in the site and pair mean field approximations, and by Monte Carlo simulations. The phase diagram of the model displays a line of continuous phase transitions between active and poisoned states, and we determined the critical exponents, β and ν⊥ of the model. Our results indicate that the critical behavior of the model does not change with the reactivity rate, and it belongs to the directed percolation universality class.