The effect of NaK ion exchange on copper states in sodium-silicate glasses containing CuO

Abstract EPR and optical spectra of copper-containing glass plates subjected to Na + K + thermal ion exchange are studied. It is shown that the shift of the valence equilibrium of copper in surface layers occurs during Na + K + ion exchange. The influence of the impurities in the melt on the shift is discussed. The EPR and optical spectroscopy of the transition metal is believed to be a very sensitive technique in order to study the details of the process of ion exchange diffusion in glasses.