Electrostatic Free Energy of Ion Transfer

It was first pointed out by Bom et that the electrostatic free energy of 1 mol of ions of radius r can be calculated on the basis of Coulomb s law if we assume that the medium surrounding the ions (solvent or polymer) is a homogeneous dieleCtric  

The situation becomes quite different when the polymer is more polar. First the dielectric constant is higher (if polar groups have sufficient local mobility so that they can adjust their orientation to the electric field). Second polar groups interact specifically witlh water so that water is partitioned into the polymer matrix and raises the effective value of further. Third polar groups and the incorporated solvent are likely 

Ions can also be partitioned into the polymer phase as ion pairs. In this case the electrostatic free energy of the ion pair, say, KX, in a homogeneous dielectric is smaller than the sum ijl% + This is due to the energy loss associated with the approach between the anion and the cation (Coulomb s law). Electrostatic free energy of the ion pair can be estimated 

---