The charge state of copper impurity atoms in AgCl annealed in vacuum or chlorine

Cu-67(Zn-67) emission Mossbauer spectroscopy and measurements of the Cu-64 decay rate have shown that copper impurity atoms occupying cation sites of the AgCl lattice are in the Cu+ state when AgCl single crystals are doped w ith Cu by diffusion in a vacuum. By contrast, diffusion in a Cl-2 atmospher e leads to partial transition of copper to the Cu2+ State and to associatio n of Cu2+ with cation vacancies. The dependence of the copper impurity char ge on the ambient atmosphere in annealing of AgCl crystals is explained by the effect of the atmosphere on the concentration of cation vacancies.