Capillary equilibria of dislocated crystals

It is shown that a dislocation whose Burgers vector exceeds a critical value, of the order of magnitude 10A., is only in equilibrium with an empty tube at its core.This is not the case in metals or other simple crystalline solids, but is likely to be the case in protein crystals, which therefore, unfortunately, do not provide good models of simple crystalline substances in respect of dislocations.The same causes generally give rise to a dimple or crater where a dislocation meets a free surface, and the shape of this crater is calculated.Though shallow in form, it is infinitely deep except at a habit face of a crystal, where it is of finite depth and may be totally absent.