Potential across the compact double layer

Having now developed the jellium-sphere model, we may compare it with the classical model. From Eqns. 5-34, 5-35 and 5-36, the potential, 4 h, across the compact layer is given by Eqn. 5-38  

The first term on the right hand side of Eqn. 5-38 is here expressed by - the second term by + z, and the integral constant of the two terms by x (a = 0) then, we obtain Eqn. 5-39  

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