Format

Send to

Choose Destination
See comment in PubMed Commons below
J Colloid Interface Sci. 2009 Nov 15;339(2):533-41. doi: 10.1016/j.jcis.2009.06.051. Epub 2009 Jun 27.

Comparison of molecular dynamics simulations with triple layer and modified Gouy-Chapman models in a 0.1M NaCl-montmorillonite system.

Author information

1
BRGM, French Geological Survey, Orléans, France. c.tournassat@brgm.fr

Abstract

Molecular dynamics (MD) simulations of a montmorillonite/water interface at the pore scale were carried out at 0.1molL(-1) NaCl concentration in order to constrain cation, anion, and water distribution and mobility influenced by the mineral surface. MD results enabled anion exclusion and cation condensation at the surface to be quantified. MD-derived values could then be compared with macroscopic model results obtained from the Modified Gouy-Chapman (MGC) theory. While the Na concentration profile is well reproduced in the diffuse layer, anion exclusion is overestimated by the MGC theory under our experimental conditions. We also showed that MD simulations can be used to constrain Basic Stern model parameters or, in combination with zeta potential measurements, can be used to constrain triple layer model (TLM) parameters by providing suitable values for the capacitance values. Na sorption intrinsic equilibrium constant values for clay basal surfaces are given accordingly.

PMID:
19683248
DOI:
10.1016/j.jcis.2009.06.051
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center