Critical Behaviour of Irreversible Reaction Systems

An introductory review on the critical behaviour of some irreversible reaction systems is given. The study of these systems has attracted great attention during the last decades due to, on the one hand, the rich and complex underlying physics, and on the other hand, their relevance for numerous technological applications in heterogeneous catalysis, corrosion and coating, development of microelectronic devices, etc. The review is focuses on recent advances in the understanding of irreversible phase transitions (IPT's) providing a survey of the theoretical development of the field during the last decade, as well as a detailed discussion of relevant numerical simulations. The Langevin formulation for the treatment of second-order IPT's is discussed. Different Monte Carlo approaches are also presented in detail and the finite-size scaling analysis of second-order IPT's is described. Special attention is devoted to the description of recent progress in the study of first-order IPT's observed upon catalytic oxidation of carbon monoxide and the reduction of nitrogen monoxide, using lattice gas reaction models. Only brief comments are given on other reactions such as the oxidation of hydrogen, ammonia synthesis, etc. Also, a discussion of relevant experiments is presented and measurement are compared with the numerical results. Furthermore, promising areas for further research and open questions are also addressed.