# Microscopic Origin of the Hofmeister Effect in Gelation Kinetics of Colloidal Silica Source: [Microscopic Origin of the Hofmeister Effect in Gelation Kinetics of Colloidal Silica]() Collection index: [llms.txt]() Data updated: 2025-10-28T13:53:45.027Z Authors: Marte van der Linden, Breannd\\'an O. Conch\\'uir, Elisabetta Spigone, Arun Niranjan, Alessio Zaccone, Pietro Cicuta Published: 2015-08-27T20:19:31.000Z ## Abstract The gelation kinetics of silica nanoparticles is a central process in physical chemistry, yet it is not fully understood. Gelation times are measured to increase by over 4 orders of magnitude, simply changing the monovalent salt species from CsCl to LiCl. This striking effect has no microscopic explanation within current paradigms. The trend is consistent with the Hofmeister series, pointing to short-ranged solvation effects not included in the standard colloidal (DLVO) interaction potential. By implementing a simple form for short-range repulsion within a model that relates the gelation timescale to the colloidal interaction forces, we are able to explain the many orders of magnitude difference in the gelation times at fixed salt concentration. The model allows us to estimate the magnitude of the non-DLVO hydration forces, which dominate the interparticle interactions on the length scale of the hydrated ion diameter. This opens the possibility of finely tuning the gelation time scale of nanoparticles by just adjusting the background electrolyte species ## Recorded benchmark results A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage. ## Original sources and implementation [Original paper]() [PDF]()