The dynamics and mechanism of migration of a vacancy point defect in a two-dimensional colloidal crystal were studied using numerical simulations. It was found that the migration of a vacancy was always realized by topology switching between its different configurations. From the temperature dependence of the topology switch frequencies, the activation energies for possible topology transitions associated with the vacancy diffusion in the two-dimensional crystal were obtained.

Mechanism of Point-Defect Diffusion in a Two-Dimensional Colloidal Crystal. L.C.DaSilva, L.Cândido, G.Q.Hai, O.N.Oliveira: Applied Physics Letters, 2011, 99[3], 031904