DYNAMIC SCATTERING FUNCTION OF A SEMIDILUTE SUSPENSION OF HARD-SPHERES

We study the time-dependent intermediate scattering function of a semidilute colloidal suspension of hard spheres with neglect of hydrodynamic interactions. The dynamics of the suspension is assumed to be governed by the generalized Smoluchowski equation. The Laplace transform of the scattering function involves the static structure factor and an irreducible memory kernel. The latter is approximated by the first term of its expansion in powers of volume fraction. The time-dependent scattering function is found by integration over the spectrum of relaxation rates.