Screening of hydrodynamic interactions for polyelectrolytes in salt solution

TL;DR

This study uses computer simulations and analytical models to show that hydrodynamic interactions in salt solutions are screened for charged polymers on short timescales, with a crossover to hydrodynamic behavior at very short times.

Contribution

It provides numerical and analytical evidence that hydrodynamic interactions are screened in polyelectrolytes in salt solutions on certain timescales, advancing understanding of polymer dynamics.

Findings

Hydrodynamic interactions are screened below the Zimm time.

A crossover to hydrodynamic behavior occurs at very short times.

Simulations and analytical models support the screening effect.

Abstract

We provide numerical evidence that hydrodynamic interactions are screened for charged polymers in salt solution on time scales below the Zimm time. At very short times, a crossover to hydrodynamic behavior is observed. Our conclusions are drawn from extensive coarse-grained computer simulations of polyelectrolytes in explicit solvent and explicit salt, and discussed in terms of analytical arguments based on the Debye-Hueckel approximation.