Single compound layer short conclusions

Solid-state growth of the layer of any chemical compound ApBq between two mutually insoluble elementary substances A and B is due to two parallel partial chemical reactions proceeding at its interfaces, each of which takes place in the two consecutive, continuously alternating steps  

Both reactions as well as the diffusional fluxes of the components across the bulk of a growing compound layer are independent of each other. 

There are two critical values, and x n2], of the layer thickness which divide this dependence into the reaction controlled and diffusion controlled regions with regard to components A and B, respectively. 

Different diffusional contributions of the components of a chemical compound to the growth process of its layer at the interface between phases A and B should not be regarded as a manifestation or result of the Kirkendall effect since the fact that these contributions are in general different became known far before discovering this effect, the essence of which consists in different diffusivities of the components of a substitutional solid solution. 

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