2005/07/22 by Ali Naji, Rudolf Podgornik · 3 citations
Chemistry · Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Characterization and Applications of Magnetic Nanoparticles #Electrostatics and Colloid Interactions #Geophysical and Geoelectrical Methods #cond-mat.dis-nn #cond-mat.soft
paper · pdf · doi:10.1103/physreve.72.041402
published as Phys. Rev. E 72, 041402 (2005) · 13 pages, 2 figures
arxiv created 2005/07/22 · openalex publication_date 2005/10/18 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We develop a general formalism to investigate the effect of quenched fixed charge disorder on effective electrostatic interactions between charged surfaces in a one-component (counterion-only) Coulomb fluid. Analytical results are explicitly derived for two asymptotic and complementary cases: (i) mean-field or Poisson-Boltzmann limit (including Gaussian-fluctuations correction), which is valid for small electrostatic coupling, and (ii) strong-coupling limit, where electrostatic correlations mediated by counterions become significantly large as, for instance, realized in systems with high-valency counterions. In the particular case of two apposed and ideally polarizable planar surfaces with equal mean surface charge, we find that the effect of the disorder is nil on the mean-field level and thus the plates repel. In the strong-coupling limit, however, the effect of charge disorder turns out to be additive in the free energy and leads to an enhanced long-range attraction between the two surfaces. We show that the equilibrium interplate distance between the surfaces decreases for elevated disorder strength (i.e., for increasing mean-square deviation around the mean surface charge), and eventually tends to zero, suggesting a disorder-driven collapse transition.