Van der Waals–Like Instability in Suspensions of Mutually Repelling Charged Colloids

Abstract

We show theoretically that the purely repulsive screened-Coulomb (or Derjaguin-Landau-Verwey-Overbeek) interaction between charged colloidal particles is compatible with gas-liquid, gas-solid, and solid-solid coexistence in colloidal suspensions of low ionic strength of about ${10}^{\ensuremath{-}6}\mathrm{mol}/\mathrm{liter}$. This finding may partially resolve the ongoing debate on attractions between like-charged particles.