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Repulsion between oppositely charged macromolecules or particles

Trulsson, Martin LU ; Jönsson, Bo LU ; Åkesson, Torbjörn LU ; Forsman, Jan LU and Labbez, Christophe LU (2007) In Langmuir 23(23). p.11562-11569
Abstract
The interaction of two oppositely charged surfaces has been investigated using Monte Carlo simulations and approximate analytical methods. When immersed in an aqueous electrolyte containing only monovalent ions, two such surfaces will generally show an attraction at large and intermediate separations. However, if the electrolyte solution contains divalent or multivalent ions, then a repulsion can appear at intermediate separations. The repulsion increases with increasing concentration of the multivalent salt as well as with the valency of the multivalent ion. The addition of a second salt with only monovalent ions magnifies the effect. The repulsion between oppositely charged surfaces is an effect of ion-ion correlations, and it increases... (More)
The interaction of two oppositely charged surfaces has been investigated using Monte Carlo simulations and approximate analytical methods. When immersed in an aqueous electrolyte containing only monovalent ions, two such surfaces will generally show an attraction at large and intermediate separations. However, if the electrolyte solution contains divalent or multivalent ions, then a repulsion can appear at intermediate separations. The repulsion increases with increasing concentration of the multivalent salt as well as with the valency of the multivalent ion. The addition of a second salt with only monovalent ions magnifies the effect. The repulsion between oppositely charged surfaces is an effect of ion-ion correlations, and it increases with increasing electrostatic coupling and, for example, a lowering of the dielectric permittivity enhances the effect. An apparent charge reversal of the surface neutralized by the multivalent ion is always observed together with a repulsion at large separation, whereas at intermediate separations a repulsion can appear without charge reversal. The effect is hardly observable for a symmetric multivalent salt (e.g., 2:2 or 3:3). (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Langmuir
volume
23
issue
23
pages
11562 - 11569
publisher
The American Chemical Society
external identifiers
  • wos:000250584500039
  • scopus:36248956225
ISSN
0743-7463
DOI
10.1021/la701222b
language
English
LU publication?
yes
id
d345eaf8-b69c-4c2d-a765-bd22d43161b2 (old id 653065)
date added to LUP
2008-01-03 11:17:29
date last changed
2017-11-12 03:25:59
@article{d345eaf8-b69c-4c2d-a765-bd22d43161b2,
  abstract     = {The interaction of two oppositely charged surfaces has been investigated using Monte Carlo simulations and approximate analytical methods. When immersed in an aqueous electrolyte containing only monovalent ions, two such surfaces will generally show an attraction at large and intermediate separations. However, if the electrolyte solution contains divalent or multivalent ions, then a repulsion can appear at intermediate separations. The repulsion increases with increasing concentration of the multivalent salt as well as with the valency of the multivalent ion. The addition of a second salt with only monovalent ions magnifies the effect. The repulsion between oppositely charged surfaces is an effect of ion-ion correlations, and it increases with increasing electrostatic coupling and, for example, a lowering of the dielectric permittivity enhances the effect. An apparent charge reversal of the surface neutralized by the multivalent ion is always observed together with a repulsion at large separation, whereas at intermediate separations a repulsion can appear without charge reversal. The effect is hardly observable for a symmetric multivalent salt (e.g., 2:2 or 3:3).},
  author       = {Trulsson, Martin and Jönsson, Bo and Åkesson, Torbjörn and Forsman, Jan and Labbez, Christophe},
  issn         = {0743-7463},
  language     = {eng},
  number       = {23},
  pages        = {11562--11569},
  publisher    = {The American Chemical Society},
  series       = {Langmuir},
  title        = {Repulsion between oppositely charged macromolecules or particles},
  url          = {http://dx.doi.org/10.1021/la701222b},
  volume       = {23},
  year         = {2007},
}