Onsager’s law

More generally, KUSCER points out that owing to the self-adjointness of the surface scattering operator, which can be defined from (2.49), the array ajj is symmetric, which may be regarded as an example of Onsager s law for... 

The deviation from Onsager s law is due to ion-ion interactions and is more pronounced for highly charged ions at high concentrations. The attractive interactions between opposite charged ions could yield to ion association, which is not exphcitly taken into account in the Onsager theory of conductivity. 

A. Katchalski and P.S. Curan 1967 The Phenomenological Equations Relating Flows and Forces Onsager s Law in Nonequilibrium Thermodynamics in Biophysics, Harvard University Press, Cambridge, MA, Ch. 8, pp. 88-91. 

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