Video-Based Kinetic Analysis of Period Variations and Oscillation Patterns in the Ce/Fe-Catalyzed Four-Color Belousov-Zhabotinsky Oscillating Reaction

The development of a video-based method for the measurement of the kinetics of oscillating reactions is described in this chapter. The method mimics reflection ultraviolet-visible spectroscopy and allows for simultaneous measurement at any target color (RC, GC, BC) with a temporal resolution of 0.01 s. The image analysis results in discrete time traces [DCC(t, RC, GC, BC)], and numerical methods are described for the analysis of the quasiperiodic oscillation patterns over the course of the reactions to determine period lengths PT(t) and other parameters [oxidation times OT(t), reduction times RT(t), etc.] that characterize the redox chemistry of the catalysts within each period. The methods were demonstrated with studies of the Ce/Fe-catalyzed four-color Belousov-Zhabotinsky reactions. The temporal evolution of period and pattern characteristics are described with polynomials, and values measured for reaction times of approximately 500 and 2000 s are discussed to highlight the temporal changes. The measurements provide a wealth of constraints to determine chemically reasonable reaction models. The discovery of the Bactrian-type oscillation pattern of ferriin in the four-color Belousov-Zhabotinsky reactions is a key result of the present study: the concentration of Fe 3+ goes through two maxima in every period