Rheology and internal dynamics of colloidal gels from the dilute to the concentrated regime

We explore the relations between dynamical, rheological and structural properties of colloidal gels extending the range previously considered towards higher particle volume fractions . Up to the spectrum of the time-dependent mean-square displacement is shown to be fully described by models accounting for the fractal character of gels. Beyond that, the direct relations between structural and stress-bearing properties used in fractal descriptions do not hold anymore. However, by considering the concepts of passive tracer rheology we show that the macroscopic shear modulus G0 can be derived from the dynamical properties up to even higher volume fractions.