USE OF DYNAMICALLY ADAPTIVE-GRID TECHNIQUES FOR THE SOLUTION OF ELECTROCHEMICAL KINETIC-EQUATIONS .4. THE ADAPTIVE MOVING-GRID SOLUTION OF ONE-DIMENSIONAL FAST HOMOGENEOUS REACTION-DIFFUSION PROBLEMS WITH EXTREMELY THIN REACTION ZONES AWAY FROM THE ELECTRODES

The adaptive moving-grid strategy suggested in Parts 1-3 for the solut ion of electrochemical kinetic partial differential equations in one s pace dimension has been subject to further evaluation and tuning. The strategy has been applied to two kinetic examples of fast homogeneous reaction-diffusion systems involving extremely thin moving reaction zo nes away from the electrodes. One example, the simulation of the doubl e-potential step transient for a simple mechanism of electrogenerated chemiluminescence, has been considered in much detail. As the second e xample the simulation of the linear potential scan voltammetry for a d ouble-electron transfer with ''nuances'' has been briefly discussed. T he adaptive grid strategy provides effective, satisfactorily accurate and complete solutions to these difficult problems, which would not be possible to obtain by traditional fixed-grid finite difference method s, except at much higher computational cost or with radical simplifica tions.