Macroion correlation effects in electrostatic screening and thermodynamics of highly charged colloids.
We study macroion correlation effects on the thermodynamics of highly charged colloidal suspensions using a mean-field theory and primitive model computer simulations. We suggest a simple way to include the macroion correlations into the mean-field theory as an extension of the renormalized jellium model of Trizac and Levin [Phys. Rev. E 69, 031403 (2004)]. The effective screening parameters extracted from our mean-field approach are then used in a one-component model with macroions interacting via a Yukawa-like potential to predict macroion distributions. We find that inclusion of macroion correlations leads to a weaker screening and hence smaller effective macroion charge and lower osmotic pressure of the colloidal dispersion as compared to other mean-field models. This result is supported by comparison to primitive model simulations and experiments for charged macroions in the low-salt regime, where the macroion correlations are expected to be significant.
Castañeda-Priego
R
R
Instituto de Física, Universidad de Guanajuato, Loma del Bosque 103, 37150 León, Mexico. ramoncp@fisica.ugto.mx
Rojas-Ochoa
L F
LF
Lobaskin
V
V
Mixteco-Sánchez
J C
JC