Abstract
Grain boundary of polystyrene latex and gold sol crystals were observed by a light microscope. Ordered boundary structures were observed. Brownian motion of the particles in the boundary suggested that the diffusion along the boundary of metals differs largely from that in the lattice. The elementary process of the boundary diffusion was in the form of an “avalanche” involving a chain of particles. Thermally activated boundary phenomena such as diffusion, migration and sliding may be understood as physical quantities produced by the same elementary process.
