POSSIBLE LOCALIZATION OF ELECTRONS AT DISLOCATIONS, DISCLINATIONS, AND GRAIN-BOUNDARIES IN METALS

The electronic structure of defects of various types in hexagonal and square lattices has been studied numerically. It is found that this structure is governed primarily by the core of the defect, rather than by the long-range part of the deformation potential. The conditions for localization of electrons depend on the type of lattice, the nature of the decay of the transport integrals, and the ''local'' symmetry of the defect. A study of disclinations shows that a fivefold axis promotes localization, in contrast with a sevenfold axis.