Charge and Size Polydispersity Effects on the Scattering Properties and the High-Frequency Elasticity of Colloids

ABSTRACTPolydispersity in charge and in size of colloidal particles strongly influences the static light scattering < I(k) >. These effects are calculated by solving the Ornstein-Zernike integral equation together with the thermodynamically consistent Rogers-Young closure for a multicomponent mixture of up to 10 components. The results for < I(k) > for polydisperse systems show significant differences from results obtained by treating the system as an effective monodisperse one. For <I(k) > a large increase is found at small k as well as a shift in the main peak. Finally, using the above results, high-frequency elastic moduli are predicted for a binary mixture.