Abstract
We discuss the design of reaction-diffusion systems that display a variety of spatiotemporal patterns. We also consider how these patterns may be controlled by external perturbation, typically using photochemistry or temperature. Systems treated include the Belousov-Zhabotinsky (BZ) reaction, the chlorite-iodide-malonic acid and chlorine dioxide-malonic acid-iodine reactions, and the BZ-AOT system, i.e., the BZ reaction in a water-in-oil reverse microemulsion stabilized by the surfactant sodium bis(2-ethylhexyl) sulfosuccinate (AOT).
The initial instances of phenomena such as chemical oscillation, traveling waves, and Turing patterns in chemically reactive media were discovered by serendipity. Once one gains an understanding of the underlying dynamics of such phenomena, even at a relatively crude level, it becomes feasible to design new systems that exhibit these behaviors and to control the patterns they display. We discuss here some approaches to generating selected spatiotemporal behaviors in reaction-diffusion systems and then look at how external influences, particularly light and temperature, may be employed to control these patterns.