2008/08/19 by B Dünweg, B. Duenweg, V. Lobaskin +5 · 1 citation
Chemistry · Earth and Planetary Sciences · Engineering · Mathematics · Physics and Astronomy · #Basis (linear algebra) #Boundary value problem #Capillary electrophoresis #Charge (physics) #Charge density #Chemistry #Chromatography #Dimensionless quantity #Electrokinetic phenomena #Electrophoresis #Electrostatics and Colloid Interactions #Finite element method #Geometry #Geophysical and Geoelectrical Methods #Materials science #Mathematics #Nanopore and Nanochannel Transport Studies #Nanotechnology #Physics #Quantum mechanics #Statistical physics #Surface charge #Thermodynamics #cond-mat.soft #cond-mat.stat-mech
paper · pdf · doi:10.1088/0953-8984/20/40/404214
To appear in Journal of Physics: Condensed Matter - special issue on occasion of the CODEF 2008 conference
arxiv created 2008/08/19 · openalex publication_date 2008/09/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Abstract. We consider electrophoresis of a single charged colloidal particle in a finite box with periodic boundary conditions, where added counterions and salt ions ensure charge neutrality. A systematic rescaling of the electrokinetic equations allows us to identify a minimum set of suitable dimensionless parameters, which, within this theoretical framework, determine the reduced electrophoretic mobility. It turns out that the salt–free case can, on the Mean Field level, be described in terms of just three parameters. A fourth parameter, which had previously been identified on the basis of straightforward dimensional analysis, can only be important beyond Mean Field. More complicated behavior is expected to arise when further ionic species are added. However, for a certain parameter regime, we can demonstrate that the salt-free case can be mapped onto a corresponding system containing additional salt. The Green–Kubo formula for the electrophoretic mobility is derived, and its usefulness demonstrated by simulation data. Finally, we report on finite–element solutions of the electrokinetic equations, using the commercial software package COMSOL. PACS numbers: 82.45.-h,82.70.Dd,66.10.-x,66.20.+d