Scattering from charged macromolecules. - I. Static structure factor

In this paper we investigate the variation of the coherent static structure factor S(q) with momentum transfer q for a solution of charged macromolecules at finite concentration with and without added salt. We consider in particular the cases of spherical and rodlike macromolecules. We introduce an effective potential model to account for the Coulomb repulsion between macromolecular ions and thence, we are able to interpret the peak observed experimentally in S(q) using a simple correlation hole argument.