Periodic precipitation and coarsening waves: Applications of the competitive particle growth modela)

Abstract

It has been shown earlier that the competitive growth dynamics of particles in a sol can account for spontaneous precipitation patterns that arise as a uniform sol ages. Here it is found that this dynamics can, unlike the classic Ostwald–Prager theory, account for a complete range of precipitation pattern types including Runge–Liesegang bands, invert bands, secondary banding, spontaneous pattern formation from a uniform sol and propagation, and destabilization of fronts of coarsening. Effects of electrical fields on banding are also investigated. A characteristic length is obtained and is found to be a strictly nonlinear effect.