A new class of critical exponents in a dimer-monomer catalytic surface reaction

Abstract

The critical behaviour of a dimer-monomer (BC+A to 1/2C2+AB) irreversible catalytic surface reaction is investigated by means of Monte Carlo simulation technique. On a hexagonal lattice (each site having six nearest neighbours), the reaction exhibits a steady reactive state between two critical concentrations yA1 and yA2 of A. The critical exponents associated with various order parameters (i.e. coverages) at the second-order phase transition yA1 have been obtained. These exponents do not fall in the universality class of Reggeon field theory as is the case of 1/2B2+A to AB, the usual dimer-monomer reaction.