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Equilibrium Structure and Properties of Model Colloidal Suspensions

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Author Affiliations

  • 1 Department of Chemistry, Birla Institute of Technology and Science, Pilani – K.K. Birla Goa Campus, Zuarinagar, Goa, INDIA

Res. J. Recent Sci., Volume 2, Issue (ISC-2012), Pages 61-66, February,2 (2013)

Abstract

We report the numerical results on the structure and properties of model colloidal suspensions using the hypernetted-chain (HNC) integral equation due to Allnatt, which has been successfully, applied to asymmetrical electrolyte solutions. We use the primitive model and view our system as highly asymmetrical electrolyte; the colloidal spheres are much larger and more highly charged than the simple ions. The variation of static correlation functions, structure factors and properties, (e.g. excess energies, osmotic coefficients etc.), is reported as a function of size, charge and concentration of colloidal particle. The peak position and the peak height of correlation functions show systematic trends as the asymmetry (in size, charge) increases. The effective one-component potential of the colloid (Veff), calculated by mapping the multicomponent system to an effective one-component colloidal system, is purely repulsive in line with the DLVO potential (with substantial deviations) in most of the cases. However, in some cases (with high asymmetry in charge and size, and at high colloidal concentration), Veff becomes negative.

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