SIMULATION FOR ORDERED STRUCTURE OF COAGULATED PARTICLES

Two-dimensional ordering of uniform spherical particles on a surface caused by Brownian motion is simulated by use of the Monte Carlo method, where the hydrodynamic interaction and potential between particles are taken into account. It is predicted that particles coagulated in the secondary minimum of the interparticle potential form either an ordered, a disordered or a dispersed structure, and that the ordering is obtained in the region of the electrolyte concentration where the interparticle potential has a relatively shallow secondary minimum. This dependence of ordering on the electrolyte concentration is compared with experimental results reported elsewhere.6) The reason why particles in the secondary minimum do not necessarily form and ordered structure is also discussed.