Modelled ions, described by non-polarizable force felds, can suffer from unphysical 
ion pairing and clustering in aqueous solutions well below their solubility limit. The
electronic continuum correction takes electronic polarization effect of the solvent into
account in an caling the charges on the ions, resulting in a much better
description of the ionic behavior. Here, we present parameters for the sodium ion con-
sistent with this effective
polarizability approach and in agreement with experimental
data from neutron scattering, which could be used for simulations of complex aqueous
systems where polarization ere important.