The 60° dislocation in diamond and its dissociation

The perfect 60degrees glide dislocation in diamond serves as an example of how different aspects of dislocations can be modelled in an approach combining continuum elasticity theory with atomistic density-functional-based tight-binding calculations. After investigating the perfect 60degrees dislocation and its isolated Shockley partials, the energetics of dissociation are discussed. The 60degrees dislocation is found to dissociate with a substantial lowering of its line energy. However, an energy barrier to dissociation is found. The glide motion of the 30degrees Shockley partial involved is modelled in a process involving the thermal formation and subsequent migration of kinks along the dislocation line.