Random motion is not attained

As a result of the assumption that random motion is not attained, a consistent treatment should allow, in principle, the possibility that electrostatic interactions could be sufficiently large to result in some ion pairing. This is likely for ions of high charge type and for those ions which just happen to be close together, and the model must therefore be modified. This has been carried out by Bjerrum and others (see Section 10.12). 

As mentioned above, the model has to be extended to take account of the short range coulombic interactions of ion pairs over and above the long range coulombic interactions of the ionic atmosphere dealt with in the theory. 

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