Kinetic phase transition in a one component irreversible reaction model

T. Aukrust, Bergen Scientific Centre
I. Webman, Bergen Scientific Centre
D. A. Browne, Louisiana State University

Abstract

Irreversible many particle dynamical systems are relevant to a broad scope of phenomena in physics, chemistry and biology. We present a study of an irreversible kinetic reaction model for a one component autocatalytic reaction A + A → A2. The system is updated as follows: If an atom adsorbed on a lattice has any neighbors it reacts with one of them with a probability (1 - p), and the two atoms leave the lattice, else the atom remains adsorbed. As p is varied, the adsorbed atoms undergo a second order kinetic phase transition from a chemically active partially covered state to a completely covered state which corresponds to the "poisoning" phenomenon seen on catalysts. The transition is studied both numerically and theoretically to gain more understanding of kinetic phase transitions and to find new methods to describe them. Finite size scaling analysis of the critical behavior has been carried out, and critical and dynamical exponents are found. The critical exponents are found to be consistent with the critical exponents in the Reggeon field theory/directed percolation universality class. © 1990 IOP Publishing Ltd.