Modifed Thomas Algorithm for the Digital Simulation of the Catalytic EC' Mechanism Under Cottrellian Conditions

Until 1991, the simulation of coupled systems, in which electrochemical reactions are coupled with homogeneous chemical reactions in such a way that at least some of the relevant partial differential transport equations (pdes) contain terms for more than one species, was considered hard. The reason is that many such reaction mechanisms lead to thin reaction layers [1], necessitating the use of very small spatial intervals near the electrode. This brings with it the need for implicit methods of solution, and so the discrete system of equations generated from the pdes became a challenge to solve. Details of this problem can be read in [2]. It is best to present an example of such a system, before describing a solution to the problem. This system is the application of a Cottrellian potential jump to the catalytic reaction pair