Dislocation Core Properties in Bulk and Layered Materials

The dislocation core is now recognised as a major contributor to many physical properties in bulk materials, for example the plasticity of metals. Less well known is that the dislocation core can be similarly important in two-dimensional (2D) systems such as surface films. Core properties in bulk materials are reviewed briefly, with emphasis on the diversity of behavior and on unifying concepts. Dislocation cores in 2D matter are considered in more detail, with particular reference to the role of the dislocation core in the melting transition.