Oxygen Semi-permeability of Oxide Electrolytes

In the absence of interactions between defects, the following reactions determine the defect concentrations in oxides with the fluorite structure. 

The electronic conductivity, comprising p-and n-type contributions, is obtained by multiplying each of the concentrations with their respective charge and mobility. Upon substitution of the defect concentrations established by the above equilibria in the electroneutrality relation, 

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