AB-INITIO THEORY OF DISLOCATION INTERACTIONS - FROM CLOSE-RANGE SPONTANEOUS ANNIHILATION TO THE LONG-RANGE CONTINUUM-LIMIT

Parallel supercomputer technology now permits ab initio studies of sys tems of sufficient size to explore the interactions among dislocations in a solid. This study shows that the silicon shuffle-set (110) screw dislocation is stable against spontaneous dissociation, provides an a b initio value for the dislocation core energy, demonstrates a disloca tion-antidislocation interaction approaching the classical limit withi n a few tens of angstroms, and reveals a pathway for the spontaneous m utual annihilation of a dislocation dipole of the type that occurs whe n a Frank-Read source emits a dislocation loop.