# Project B2

## Electrokinetic Properties of Charged Colloids in External Fields

### Project leaders

### Summary

Progressing from our work done in the second funding period, we plan to calculate the steady-state dynamic structure factor, measured by superheterodyne Doppler velocimetry, of dispersions of interacting colloids in external electric, gravitational and shear-flow fields. We will analyze the relations between the dynamic structure factor and transport coefficients such as the electrophoretic mobility, sedimentation velocity and diffusion coefficients. Furthermore, we want to extend the superheterodyne scattering theory to colloidal mixtures. In a second topic, we will study the electrokinetic influence of salt ions on the shear viscosity in non-dilute suspensions. Thirdly, the dynamics of colloidal mixtures is explored, particularly the sensitivity of the viscosity to compositional changes.