Scroll-Shaped Waves of Chemical Activity in Three Dimensions

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Science  07 Sep 1973:
Vol. 181, Issue 4103, pp. 937-939
DOI: 10.1126/science.181.4103.937


Ferric ions catalyze the oxidation of malonate by bromate in acid solution, sometimes at a spatially uniform, steady rate, but sometimes in a self-regenerating three-dimensional wave which resembles a rotating scroll, often with its axis closed in a ring. In cross section perpendicular to the axis, one sees an involute spiral emerging from a thin cylindrical core. This "dissipative structure" organizes reaction stages periodically in space and time everywhere except along its rotation axis, which may therefore be a thermodynamically unique locus.