BZ Oscillating Reactions

Abstract

The reaction known as the Belousov-Zhabotinskii reaction is an important oscillating reaction discovered by the Russian Boris Belousov (1951), a biochemist, and is described in an unpublished paper, which was contemptuously rejected by a journal editor; at the time the accepted dogma was that oscillating reactions were simply not possible. A translation of the original article is given in the book edited by Field and Burger (1985). Eventually Belousov (1959) published a brief note in the obscure proceedings of a Russian medical meeting. Basically he found oscillations in the ratio of concentrations of the catalyst; in Belousov’s reaction it was cerium in the oxidation of citric acid by bromate. The oscillation manifested itself via a colour change as the cerium changed from Ce3+ to Ce4+ although it is more dramatic with an iron ion, ferroin where the colour is brick red when in the Fe2e state and bright blue in the Fe3e state. The study of this reaction was continued by Zhabotinskii (1964) and is now known as the Belousov-Zhabotinskii reaction or simply the BZ reaction. When the details of this important reaction and some of its dramatic oscillatory and wavelike properties finally reached the West in the 1970’s it provoked widespread interest and research. Belousov’s seminal work was finally, but posthumously, recognised in 1980 by his being awarded the Lenin Prize. Winfree (1984) gives a brief interesting description of the history of the Belousov-Zhabotinskii reaction. When the reactants can also diffuse a diverse menagerie of complex patterns can be formed and it is the latter which has sustained the continuing widespread interest among both biological and physical scientists.