Structure of multi-component/multi-Yukawa mixtures

Abstract

Abstract. Recent small angle scattering experiments reveal new peaks in the structure function S(k) of colloidal systems ( S.H. Chen et al [1]), in a region that was inaccessible with older instruments. It has been increasingly evident that a single (or double) Yukawa MSA-closures cannot account for these observations, and three or more terms are needed. On the other hand the MSA is not sufficiently accurate with the boundary condition for g ij (r) = 0 for r ≤ σ ij . This general closure of the Ornstein Zernike equation will go well beyond the MSA since it has been tested by Monte Carlo simulation for tetrahedral water [7], toroidal ion channels [8] and polyelectrolytes [9]. For this closure we get for the Laplace transform of the pair correlation function an explicitly symmetric result is a scalar function. For polydisperse electrolytes in the MSA a simpler expression is also obtained (compare [12]) . An explicit continued fraction solution of the 1 component multiyukawa case is also given.

Jscatter, a program for evaluation and analysis of experimental data

“…An extensible environment with a model library currently focused on scattering is provided. Additional to the implemented models more form factors will be included and the structurefactor module will be extended to allow more complex structure factors as multi Yukawa potentials[69,70].…”