Absence of scaling for the intermediate scattering function of a hard-sphere suspension: Static and dynamic x-ray scattering from concentrated polystyrene latex spheres

X-ray photon correlation spectroscopy and small-angle scattering measuremen ts are presented of the dynamics and structure of concentrated suspensions of charge-stabilized polystyrene latex spheres dispersed in glycerol, for v olume fractions from 3% to 52%. The static structures of the suspensions sh ow essentially hard-sphere behavior, and the short-time dynamics shows good agreement with predictions for the wave-vector-dependent collective diffus ion coefficient, However, the intermediate scattering function is found to violate a scaling behavior found previously for a sterically stabilized har d-sphere suspension [P.N. Segre and P.N. Pusey, Phys. Rev. Lett. 77, 771 (1 996)].