Aggregation of Divalent Impurities in Sodium Chloride Doped with Cadmium

Abstract
The occurrence of remarkable precipitation phenomena of Cd additions in NaCl single crystals is studied by means of ionic thermoconductivity. An excess of impurity-cation vacancy dipoles anneals following monomolecular third-order kinetics, at temperatures ranging from 275 to 324°K. The motion parameters have been determined and are discussed. A careful investigation shows that the kinetics is more complicated during the first stage of the precipitation process.