Study and control of the N2O + H2 reaction on Ir(110) by Monte Carlo simulations
M. C. Lemos, F. E. Gálvez, A. C´ordoba
We study the reaction N2O + H2 catalyzed on an Ir(110) surface by means of Monte Carlo (MC) simulations, focusing our work on the temporal evolution of the system. The bifurcation diagram of the model, which represents the surface density of adsorbed species as a function of a parameter, shows three distinct regions: an oscillatory region, which exhibits P1 (period-1, one maximum) oscillations, between two stable steady regions. Results obtained are in good agreement with experiments conducted in the reaction.
At a later stage and to analyze the stability of the observed P1 oscillations, we apply harmonic disturbances on the MC model. To do this we perturb the P1 autonomous oscillations by periodic modulation of the partial pressure of one of the reactants and different dynamic regimes can be observed by varying the amplitude and frequency of the disturbance, whose values are used to control the behavior of the system. From the perturbed MC model interesting conclusions are drawn: when the external frequency is a half-integer of the natural frequency the oscillatory behavior becomes aperiodic and quasiperiodic. CYBERNETICS AND PHYSICS, VOL. 1, NO. 3, 2012 , 169–178.