Structure and dynamics of colloidal depletion gels: coincidence of transitions and heterogeneity

Details Structure and dynamics of colloidal depletion gels: coincidence of transitions and heterogeneity Structure and dynamics of colloidal depletion gels: coincidence of transitions and heterogeneity

2006-06-06

arxiv.org/abs/cond-mat/0606127v1

Physics

Condensed Matter

Soft Condensed Matter

14 pages, 10 figures

Scientific paper

10.1103/PhysRevE.74.041403

Transitions in structural heterogeneity of colloidal depletion gels formed through short-range attractive interactions are correlated with their dynamical arrest. The system is a density and refractive index matched suspension of 0.20 volume fraction poly(methyl methacyrlate) colloids with the non-adsorbing depletant polystyrene added at a size ratio of depletant to colloid of 0.043. As the strength of the short-range attractive interaction is increased, clusters become increasingly structurally heterogeneous, as characterized by number-density fluctuations, and dynamically immobilized, as characterized by the single-particle mean-squared displacement. The number of free colloids in the suspension also progressively declines. As an immobile cluster to gel transition is traversed, structural heterogeneity abruptly decreases. Simultaneously, the mean single-particle dynamics saturates at a localization length on the order of the short-range attractive potential range. Both immobile cluster and gel regimes show dynamical heterogeneity. Non-Gaussian distributions of single particle displacements reveal enhanced populations of dynamical trajectories localized on two different length scales. Similar dependencies of number density fluctuations, free particle number and dynamical length scales on the order of the range of short-range attraction suggests a collective structural origin of dynamic heterogeneity in colloidal gels.

Affiliated with

Also associated with

No associations

Rating

Structure and dynamics of colloidal depletion gels: coincidence of transitions and heterogeneity does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Structure and dynamics of colloidal depletion gels: coincidence of transitions and heterogeneity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Structure and dynamics of colloidal depletion gels: coincidence of transitions and heterogeneity will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-2887