中国物理B ›› 2011, Vol. 20 ›› Issue (7): 76401-076401.doi: 10.1088/1674-1056/20/7/076401

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Electrostatic interaction between a rod-like macromolecule and a circular orifice/disk in an electrolyte solution

连增菊   

  1. Department of Physics, Ningbo University, Ningbo 315211, China
  • 收稿日期:2010-12-07 修回日期:2011-01-29 出版日期:2011-07-15 发布日期:2011-07-15

Electrostatic interaction between a rod-like macromolecule and a circular orifice/disk in an electrolyte solution

Lian Zeng-Ju(连增菊)   

  1. Department of Physics, Ningbo University, Ningbo 315211, China
  • Received:2010-12-07 Revised:2011-01-29 Online:2011-07-15 Published:2011-07-15

摘要: We present the solutions of the interaction energy for a colloid system with a charged rod-like macromolecule immersed in a bulk electrolyte and moving along the axis of a circular orifice or disk (orifice/disk). The calculation requires a numerical computation of the surface charge profiles, which result from a constant surface potential on the macromolecule and the orifice/disk. In the calculation, remarkable divergences of the surface charge emerge on the edges of the macromolecule and the orifice/disk, which are well-known edge effects. The anisotropic distribution of the surface charge (effective dipole) results in an attraction between these two charged objects. This attraction is enhanced with the increase of the screening length of the system for both the orifice and the disk systems. However, the sizes of the orifice and the disk reduce to different effects on the interaction energy.

Abstract: We present the solutions of the interaction energy for a colloid system with a charged rod-like macromolecule immersed in a bulk electrolyte and moving along the axis of a circular orifice or disk (orifice/disk). The calculation requires a numerical computation of the surface charge profiles, which result from a constant surface potential on the macromolecule and the orifice/disk. In the calculation, remarkable divergences of the surface charge emerge on the edges of the macromolecule and the orifice/disk, which are well-known edge effects. The anisotropic distribution of the surface charge (effective dipole) results in an attraction between these two charged objects. This attraction is enhanced with the increase of the screening length of the system for both the orifice and the disk systems. However, the sizes of the orifice and the disk reduce to different effects on the interaction energy.

Key words: electrostatic interaction, Green's function, anistropic distribution

中图分类号:  (Colloids)

  • 64.70.pv
47.57.J- (Colloidal systems) 41.20.Cv (Electrostatics; Poisson and Laplace equations, boundary-value problems)