Use of One‐Parameter Models for the Assessment of Particle Interactions by photon correlation spectroscopy

Abstract

The use of very simple one‐parameter models of particle interactions for the analysis of the concentration dependence of the collective diffusion coefficient as determined by photon correlation spectroscopy is illustrated by measurements on two different systems. In one, a micro‐emulsion, attractive interactions are dominant whereas in the other, a silica dispersion, repulsive interactions play the major role.

A Survey of Complementary Methods for the Characterization of Dense Colloidal Silica

“…Since PCS is a technique that probes the dynamics of dispersed particles detecting the backscattered light (angle of 173°) of the suspensions, more information than particle size distribution can be obtained. In particular, for particles subjected to Brownian motion, the translational diffusion coefficient (the collective one, which describes the motion of a collection of particles) can be determined by PCS [14][15].…”

“…The values of the translational diffusion coefficient D 0 are then evaluated (see Table 2). From D 0 , the hydrodynamic diameter d H , which is the diameter of the particle plus the thickness of the layer of solvation which surrounds it, is obtained [15]:…”

Particle Sizing by Photon Correlation Spectroscopy. Part II: Average values

“…Since the Stokes-Einstein expression is not applicable in many cases (see e. g. [12]) a designation "effective diameter" is more appropriate for the average Stokes-Einstein diameters as determined with PCS.…”

Charakterisierung von Wechselwirkungseinflüssen auf die Partikeldiffusion mittels Photonenkorrelationsspektroskopie

“…Sein Ergebnis war ein erweiterter Virialansatz für den Kollektivdiffusionskoeffizienten, der auch von Finsy [24] übernommen wurde:…”