Limiting law excess sum rule for polyelectrolytes

作者:Landy Jonathan*; Lee YongJin; Jho YongSeok
来源:Physical Review E, 2013, 88(5): 052315.
DOI:10.1103/PhysRevE.88.052315

摘要

We revisit the mean-field limiting law screening excess sum rule that holds for rodlike polyelectrolytes. We present an efficient derivation of this law that clarifies its region of applicability: The law holds in the limit of small polymer radius, measured relative to the Debye screening length. From the limiting law, we determine the individual ion excess values for single-salt electrolytes. We also consider the mean-field excess sum away from the limiting region, and we relate this quantity to the osmotic pressure of a dilute polyelectrolyte solution. Finally, we consider numerical simulations of many-body polymer-electrolyte solutions. We conclude that the limiting law often accurately describes the screening of physical charged polymers of interest, such as extended DNA.

  • 出版日期2013-11-25