Intermediate States of Electrodeposition

In the model the main three surface processes are shown, which are (1) the charge transfer process, (2) surface diffusion, and (3) the transfer from the ad-atom position into a step or kink position. Not shown are the diffusion processes in the electrolyte. Each step can be rate determining, such as the charge transfer between electrolyte and metal surface (Chapter 6), surface diffusion (Chapter 4), or the transfer into a step or kink position, the final crystallization process. 

In this diagram the reaction of an ad-atom with the kink site position is reversible. But in the kink site position an atom may return to its previous position by separation from the kink site position, or it may become fixed in the crystal lattice by the next atom deposited in the kink site position. The built-in process is then completed. In this model, the kink site position has a similar function as the transition state in the theory of chemical reactions. 

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