Oscillations of chemical origin have been present as long as life itself. Every living system contains scores, perhaps hundreds, of chemical oscillators. The systematic study of oscillating chemical reactions and of the broader field of nonlinear chemical dynamics is of considerably more recent origin, however. In this chapter, we present a brief and extremely idiosyncratic overview of some of the history of nonlinear chemical dynamics. In 1828, Fechner described an electrochemical cell that produced an oscillating current, this being the first published report of oscillations in a chemical system. Ostwald observed in 1899 that the rate of chromium dissolution in acid periodically increased and decreased. Because both systems were inhomogeneous, it was believed then, and through much of our own century, that homogeneous oscillating reactions were impossible. Degn wrote in 1972 (p. 302): “It is hard to think of any other question which already occupied chemists in the nineteenth century and still has not received a satisfactory answer.” In that same year, though, answers were coming. How it took so long for the nature of oscillating chemical reactions to be understood and how that understanding eventually came about will be the major focus of this chapter. Although oscillatory behavior can be seen in many chemical systems, we shall concentrate primarily on homogeneous, isothermal reactions in aqueous solution. In later chapters, we shall broaden our horizons a bit. While the study of oscillating reactions did not become well established until the mid-1970s, theoretical discussions go back to at least 1910. We consider here some of the early theoretical and experimental work that led up to the ideas of Prigogine on nonequilibrium thermodynamics and to the experimental and theoretical work of Belousov, Zhabotinsky, Field, Körös, and Noyes, all of whom did much to persuade chemists that chemical oscillations, traveling fronts, and other phenomena that now comprise the repertoire of nonlinear chemical dynamics were deserving of serious study. Alfred Lotka was one of the more interesting characters in the history of science. He wrote a handful of theoretical papers on chemical oscillation during the early decades of this century and authored a monograph (1925) on theoretical biology that is filled with insights that still seem fresh today.
An Introduction to Nonlinear Chemical Dynamics: Oscillations, Waves, Patterns, and Chaos (Epstein, I. R.; Pojman, J. A.)
