  The response of a suspension under a variety of static or alternating
external fields strongly depends on the equilibrium electric double layer that
surrounds the colloidal particles in the suspension. The theoretical models for
salt-free suspensions can be improved by incorporating non-uniform size effects
and orientational ordering of water dipoles neglected in previous mean-field
approaches, which are based on the Poisson-Boltzmann approach. Our model
including non-uniform size effects and orientational ordering of water dipoles
seems to have quite a promising effect because the model can predict the
phenomena like a heavy decrease in relative permittivity of the suspension and
counterion stratification near highly charged colloidal particle. In this work
we numerically obtain the electric potential, the counterions concentration and
the relative permittivity around a charged particle in a concentrated salt-free
suspension corrected by non-uniform size effects and orientational ordering of
water dipoles. The results show the worth of such corrections for medium to
high particle charges at every particle volume fraction. We conclude that
non-uniform size effects and orientational ordering of water dipoles are
necessary for the development of new theoretical models to study
non-equilibrium properties in concentrated colloidal suspensions.
