Linear compounds of dislocations in silver chloride with cupric ions

Abstract

Abstract Crystals of silver chloride containing 0•1 mol % cupric chloride were annealed at temperatures just below the melting point (455°c) and then cooled. Under dark-field illumination lozenge-shaped dislocation loops were observed in them. The orientation of the loops indicates that they lie in {110} planes and that they would glide on {111} planes along <110> directions. The configurational charge of edge dislocations in silver chloride gliding in this way would normally contribute an electrostatic term to the total energy of the crystal containing dislocations. It is suggested that the configurational charge is neutralized by cupric ions which adsorb on the edge dislocations, thus forming a stoichiometric compound, so that effectively there is no electrostatic energy associated with them.