ORDER-DISORDER TRANSITION DRIVEN BY RANDOM INTERACTIONS

The role of random interactions in the disruption of crystalline order is investigated using a Monte Carlo (MC) simulation of charge polydisperse colloidal crystals. The static root-mean-square displacement of the equilibrium particle positions with respect to a reference lattice and the configurational entropy shows a jump across the order-disorder (crystalline-to-glass) transition. Lattice relaxations as a function of polydispersity are calculated analytically from a nearest neighbour model. The MC results are in good agreement with those predicted by the model.