A simple approach for charge renormalization of highly charged macro-ions

Emmanuel Trizac; Lyderic Bocquet; Miguel Aubouy

doi:10.1103/physrevlett.89.248301

Home/Archive/arXiv

arXiv · cond-mat/0201510

A simple approach for charge renormalization of highly charged macro-ions

Emmanuel Trizac·Lyderic Bocquet·Miguel Aubouy

View original source ↗Read source document ↗Export metadata ↓

Abstract

We revisit the popular notion of effective or renormalized charge, which is a concept of central importance in the field of highly charged colloidal or polyelectrolyte solutions. Working at the level of a linear Debye-Hückel like theory only, we propose a simple, efficient and versatile method to predict the saturated amount of charge renormalization, which is however a non-linear effect arising at strong electrostatic coupling. The results are successfully tested against the numerical solutions of Poisson-Boltzmann theory for polyions of various shapes (planar, cylindrical and spherical), both in the infinite dilution limit or in confined geometry, with or without added electrolyte. Our approach, accurate for monovalent micro-ions in solvents like water, is finally confronted against experimental results, namely the crystallization of charged colloidal suspensions and the osmotic coefficient of B-DNA solutions.

Explore related subjects

cond-mat.soft cond-mat.stat-mech

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Emmanuel Trizac, Lyderic Bocquet, Miguel Aubouy. 2002-10-11. A simple approach for charge renormalization of highly charged macro-ions. https://doi.org/10.1103/physrevlett.89.248301

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Deformation and organization of droplet-encapsulated soft beads

Many biological, culinary, and engineering processes lead to the co-encapsulation of several soft particles within a liquid interface. In these situations the particles are bound together by the capillary forces that deform them and influence their biological or rheological properties. Here, we introduce an experimental approach to encapsulate a controlled number of soft beads within aqueous droplets in oil. These droplet-encapsulated gels are manipulated in a deformable microfluidic device to merge them and modify the liquid fraction. In the dry limit the contact surface between the hydrogels is found to be determined by the elastocapillary number $E_c$, with the contact radius following a $E_c^{1/3}$ dependence, indicating that the deformation increases for soft or small particles. When multiple beads are co-encapsulated within a single droplet they can be arranged into linear or three-dimensional aggregates that remain at a local energy minimum.

cond-mat.soft↗

arXiv2026

Flexoelectricity-driven softening of bend elasticity leads to spontaneous chiral symmetry breaking in a polar fluid

The origin of the recently observed spontaneous chiral symmetry breaking in polar fluids composed of achiral molecules is an unsolved problem, raising fundamental questions about how heliconical structures emerge in such systems. Here, we investigate the pretransitional fluctuations leading to the formation of the spontaneously chiral twist-bend ferroelectric nematic phase using dielectric spectroscopy, light scattering, and small-angle X-ray scattering. We observe simultaneous softening of the bend elastic constant and the emergence of a collective dielectric mode on approaching the transition. By developing a theoretical model, we show that these phenomena are signatures of a flexoelectricity-driven transition arising from the coupling between electric polarization and bend deformation.

cond-mat.soft↗

arXiv2026

Taylor dispersion in a soft tube

Diffusion of a solute along a tube is enhanced by hydrodynamic flow, a phenomenon known as Taylor dispersion. In microfluidic applications, the compliance of the tube boundaries modifies the hydrodynamic flow and thus solutal transport. Here, we develop the theory of solutal dispersion in a soft, axisymmetric tube where the tube walls respond to the hydrodynamic pressure through a Winkler response. By deriving the modified macro-transport equation for the solutal concentration dynamics based on multiple-time-scale analysis, we explore the influence of softness on solutal transport for steady and pulsatile configurations. Our main finding is that softness enhances the effective advection velocity and dispersion coefficient, which might have practical implication in biology and microfluidic technology.

cond-mat.soft↗