The Debye-Huckel Theory of Ionic Solutions An Assessment

The Debye-Huckel Theory of Ionic Solutions An Assessment 

The excess charge density was taken to be given, on the one hand, by Poisson s equation of electrostatics 

The result of equating these two expressions for the excess charge density is the fundamental partial differential equation of the Debye-Hiickel model, the linearized P-B equation (Fig. 3.36), 

By assuming that ions can be regarded as point charges, the solution of the linearized P-B equation turns out to be (Fig. 3.37) 

Such a variation of potential with distance from a typical (central or reference) ion corresponds to a charge distribution that can be expressed as a function of distance r from the central ion by 

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