Therefore, inside the radius a _ i, the ion atmosphere exerts no force.
2.
By the definition of electric potential energy, the potential energy associated with the singled out ion in the ion atmosphere is
3.
D & H recognize the importance of the parameter in their paper and characterize it as a measure of the thickness of the ion atmosphere, which is an electrical double layer of the Guoy Chapman type.
4.
Since the ion atmosphere is assumed to be ( time-averaged ) spherically symmetric, with charge varying as a function of radius r, it may be represented as an infinite series of concentric charge shells.