Microscopic Grain Boundary Dynamics in Colloidal Crystals

Abstract

The dynamics of grain boundaries in two-dimensional colloidal crystals are closely related to the geometry of the boundary and the misorientation between two grains. Previous experimental research has shown that artificial loop-shaped grain boundaries show characteristic particle displacement patterns and dislocation movements. In this thesis we present Brownian dynamics simulations on similar, larger systems which show identical microscopic behaviour. We show how we can explain these observations using a novel interpretation of O-lattice theory, based solely on the geometry of the two grains, and how we can extends this theory to help predict particle displacements and dislocation movements during grain boundary loop shrinkage specifically, and arbitrarily-shaped grain boundaries in general.