Eur. Phys. J. B 40, 305-312 (2004)
https://doi.org/10.1140/epjb/e2004-00271-1

Study of a monomer-monomer reaction system with short-range repulsive interactions

Monomer-monomer reaction system with repulsive interactions

¹ Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, (INIFTA), CONICET, UNLP. Sucursal 4, Casilla de Correo 16, (1900) La Plata, Argentina
² Center for Interdisciplinary Plasma Science (CIPS), Max Planck-Institut für extraterrestrische Physik, Giessenbachstr. 1, 85748, Garching, Germany

Corresponding author: ^a roberto@cips.mpg.de

Received: 24 March 2004
Revised: 8 July 2004
Published online: 31 August 2004

Abstract

The critical behavior of an interacting two species catalytic surface reaction model is studied by means of Monte Carlo simulations and a mean-field approach. The model has two parameters, namely the relative adsorption rate of species p_A and a short-range repulsive interaction r between the same type of adsorbed species. The system exhibits an stationary reactive phase and two symmetrically equivalent absorbing phases. These latter phases are unique and correspond to surfaces saturated by a single type of reacting species. For , the system exhibits a second-order phase transition that belongs to the directed percolation (DP) universality class. However, in the absence of repulsive interaction (r = 0), a bicritical point is found at whose critical behavior is compatible with dynamical mean-field exponents. Our findings indicate that the bicritical point belongs to the Voter Model universality class, whose upper critical dimension is d_c = 2. In addition, we propose a method to study the crossover from MF to DP behavior based on the estimation of the crossover time T_c. We find that T_c diverges according to a power-law as where is the crossover exponent. For strong repulsion, a new transient effect appears associated with the onset of almost inactive “chessboad” patterns.