MICROSCOPIC FORMULATION OF A LATTICE-DEFECT MODEL

A microscopic construction method of lattice defects which can be represented by dislocation configurations in simple-cubic lattices and for interaction by central forces is given. In contrast to standard theories, where dislocations are introduced via topological operations (Burgers circuit), the author starts from a microscopic ad hoc Hamiltonian which is suitable only for central-force interacting systems. The various sectors of this microscopic Hamiltonian are associated with dislocation configurations. A detailed discussion of the stability and symmetry properties of the microscopic Hamiltonian is given. Possible extensions of the theory to non-central-force interacting systems are pointed out. © 1979 The American Physical Society.