Static structure factors of binary suspensions of charged polystyrene spheres: experiment against theory and computer simulation

Abstract

The micrcscopic Static s t ~c t u r e of dilute binary colloidal Suspensions, for w m p i l i o n s ewering the full molar fraction range, are investigated using static light scattering ffpiments. The mktures of liquid-like ordered suspensions are made from charged polystyrene particles having averaged radii 01 42 nm and 65 om. The data are compared with the results of integral equation theories using the extended re-scaled mean spherical approximation and the hypernetted chain approximation and Rogers-Young closure schemes, and to Monte Carlo computer simulations The values of charges needed in the Yukawa-type pair potentials are delermined from 615 to the scatlering data of the pure components, and they are l r p l consbnt for Ule mixtures. O f the various theoretical schemes used, the RogekYoung method is found to be the most salisfactoty. In order to fully describe the experimental data, it is necersaty to take the intrinsic polydispersity of the NK) pure componenu into account.

Nonadditivity in the effective interactions of binary charged colloidal suspensions

“…The traditional Derjaguin-Landau-Verwey-Overbeek (DLVO) theory describes the interaction between the two species as an effective pairwise Yukawa potential [16,17] V (r ) = Z i e 1 + σ i κ D /2…”

Dynamics and yielding of binary self-suspended nanoparticle fluids

“…All the samples were smeared on a thermal sample cell and the measurements were performed at 90 1C, which is above the melting point of PEG. 45,48 3. In the limit of infinite dilution, S(q,R S ,R L ,f S -0,f L -0) B 1, and the form factors can be conveniently estimated from the scattering intensities.…”

Chemical Charge Regulation and Charge Renormalization in Concentrated Colloidal Suspensions

“…For small colloidal charges, the Z* thus determined has recently been shown to reproduce results from primitive model calculations quite nicely (12). Experimentally, this concept has been used many times to describe interaction-dependent properties of colloidal suspensions such as phase behavior (13), the structure of binary mixtures (14), the diffusive dynamics (15), and electrokinetic phenomena (16).…”