Colloid dynamics and transitions to dynamically arrested states

The dynamic properties of colloidal suspensions constitute an important experimental and theoretical aspect of the study of colloidal systems [1–3]. In equilibrium, and in the absence of external fields, the most relevant dynamic information of such systems is contained in the intermediate scattering function F(k, t) [2]. This function is the spatial Fourier transform (FT) of the van Hove function G(r, t), which measures the spatial and temporal correlations of the thermal fluctuations δn(r, t) ≡ n(r, t) – n of the local concentration n(r, t) of colloidal particles at position r and time t around its equilibrium bulk average n, that is, nG(|r - r′|; t) ≡ 〈δn(r, t)δn(r′, 0)〉, where the angular brackets indicate average over the equilibrium ensemble [2]. A closely related property is the so called self intermediate scattering function F(S)(k, t). This is defined as F(S)(k, t) ≡ 〈eik ΔR(t)〉, where ΔR(t) is the displacement at time t of any of the particles of the Brownian fluid. © 2009 by Taylor %26 Francis Group, LLC.

VIVO