Simulations of surface forces in polyelectrolyte solutions.
(2008) In The Journal of Physical Chemistry Part B 112(16). p.5116-5125- Abstract
- We have simulated interactions between charged surfaces in the presence of oppositely charged polyelectrolytes by coupling perturbations in the isotension ensemble to a free energy variance minimization scheme. For polymeric systems, this method completely outperforms configurationally biased versions of grand canonical simulations. Proper diffusive equilibrium between bulk and slit has been established for polyelectrolytes with up to 60 monomers per chain. A consequence of imposing diffusive equilibrium conditions, in contrast to previous more restricted models, is the possibility of surface charge inversion; ion-ion correlation and the cooperativity of monomer adsorption drive the formation of a polyion layer close to the surface, that... (More)
- We have simulated interactions between charged surfaces in the presence of oppositely charged polyelectrolytes by coupling perturbations in the isotension ensemble to a free energy variance minimization scheme. For polymeric systems, this method completely outperforms configurationally biased versions of grand canonical simulations. Proper diffusive equilibrium between bulk and slit has been established for polyelectrolytes with up to 60 monomers per chain. A consequence of imposing diffusive equilibrium conditions, in contrast to previous more restricted models, is the possibility of surface charge inversion; ion-ion correlation and the cooperativity of monomer adsorption drive the formation of a polyion layer close to the surface, that overcompensates the nominal surface charge. This is observed even at modest surface charge densities, and leads to a build up of a long ranged electrostatic barrier. In addition, the onset of charge inversion requires very low bulk polymer densities. Due to screening effects, this leads to a higher and more long-ranged free energy barrier at low, compared to high, bulk densities. Oscillatory forces, reminiscent of those found in simple hard sphere systems, are resolved in the high concentration regime. As a consequence of a second surface charge inversion, the system "stratifies" to form a stable polyelectrolyte layer in the central part of the slit, stabilized by the adsorbed surface layers. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1147821
- author
- Turesson, Martin LU ; Woodward, Clifford E ; Åkesson, Torbjörn LU and Forsman, Jan LU
- organization
- publishing date
- 2008
- type
- Contribution to journal
- publication status
- published
- subject
- in
- The Journal of Physical Chemistry Part B
- volume
- 112
- issue
- 16
- pages
- 5116 - 5125
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000255104900037
- pmid:18386879
- scopus:46849114136
- pmid:18386879
- ISSN
- 1520-5207
- DOI
- 10.1021/jp800632e
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Theoretical Chemistry (S) (011001039)
- id
- 6a3e7eb2-45c3-4ddd-8e76-b360c50ad1ec (old id 1147821)
- date added to LUP
- 2016-04-01 14:30:42
- date last changed
- 2023-01-04 05:00:35
@article{6a3e7eb2-45c3-4ddd-8e76-b360c50ad1ec,
abstract = {{We have simulated interactions between charged surfaces in the presence of oppositely charged polyelectrolytes by coupling perturbations in the isotension ensemble to a free energy variance minimization scheme. For polymeric systems, this method completely outperforms configurationally biased versions of grand canonical simulations. Proper diffusive equilibrium between bulk and slit has been established for polyelectrolytes with up to 60 monomers per chain. A consequence of imposing diffusive equilibrium conditions, in contrast to previous more restricted models, is the possibility of surface charge inversion; ion-ion correlation and the cooperativity of monomer adsorption drive the formation of a polyion layer close to the surface, that overcompensates the nominal surface charge. This is observed even at modest surface charge densities, and leads to a build up of a long ranged electrostatic barrier. In addition, the onset of charge inversion requires very low bulk polymer densities. Due to screening effects, this leads to a higher and more long-ranged free energy barrier at low, compared to high, bulk densities. Oscillatory forces, reminiscent of those found in simple hard sphere systems, are resolved in the high concentration regime. As a consequence of a second surface charge inversion, the system "stratifies" to form a stable polyelectrolyte layer in the central part of the slit, stabilized by the adsorbed surface layers.}},
author = {{Turesson, Martin and Woodward, Clifford E and Åkesson, Torbjörn and Forsman, Jan}},
issn = {{1520-5207}},
language = {{eng}},
number = {{16}},
pages = {{5116--5125}},
publisher = {{The American Chemical Society (ACS)}},
series = {{The Journal of Physical Chemistry Part B}},
title = {{Simulations of surface forces in polyelectrolyte solutions.}},
url = {{http://dx.doi.org/10.1021/jp800632e}},
doi = {{10.1021/jp800632e}},
volume = {{112}},
year = {{2008}},
}