Introduction to the dynamic self-organization of chemical systems

Abstract

Following the presentation of basic concepts of nonlinear dynamics in chemistry in Part I, such dynamic instabilities like the oscillations, multistability, and spatiotemporal pattern formation are described in the present Part II for several real chemical systems, together with relevant kinetic models. Homogeneous systems include one of the Orban oscillators, involving catalytic oxidation of thiocyanates with hydrogen peroxide and the classical Belousov–Zhabotinsky reaction, together with its well-established Oregonator kinetic model. A heterogeneous electrochemical system involving the electroreduction of nickel thiocyanate complexes reveals bistability and oscillations interrelated as in the Boissonade–De Kepper model. Spatiotemporal patterns emerging due to the coupling between the chemical reaction and diffusion are shown based on: (1) the Belousov–Zhabotinsky reaction including its excitable characteristics, (2) the Brusselator as a source of the model Turing patterns also reported experimentally, and (3) periodic precipitation known as the Liesegang phenomena. Furthermore, the recently reported patterns formed in the systems subject to inhomogeneous temperature distribution were described. The self-organized nature of convection was shown based on both the classical Benard experiment and the convection driven electrochemically, including the “beating mercury heart” and the electrohydrodynamic formation of luminescent patterns. The course is completed with the brief description of the concept of deterministic chaos and the principle of its control as the modern subject of nonlinear dynamics. The appendix includes laboratory prescriptions for the most attractive experiments.