THE VERTEX CONTRIBUTION TO THE KIRSTE-POROD TERM

It is shown that, close to the origin, the correlation function [gamma(r)] of any N-component sample with interfaces made up of planar facets is always a third-degree polynomial in r. Hence, the only monotonically decreasing terms present in the asymptotic expansion of the relevant small-angle scattered intensity are the Pored [-2 gamma'(0(+))/h(4)] and the Kirste-Porod [4 gamma((3))(0(+))/h(6)] contributions. The latter contribution is non-zero owing to the contributions arising from each vertex of the interphase surfaces. The general vertex contribution is evaluated in closed form and the gamma((3))(0(+)) values relevant to the regular polyhedra are reported.