Exciton Absorption in Mixed Alkali Chlorides, KCl-RbCl and KCl-NaCl

Abstract

The effects of foreign alkali metal ions on the exciton absorption in some alkali chlorides have been investigated. The mixed systems of KCl-RbCl and KCl-NaCl were chosen as characteristic examples. In KCl-RbCl, positions of the exciton peaks shift fairly linearly with the change of relative concentrations of the constituents, and the ‘chlorine doublet’ keeps its structure throughout the full range of concentration. In KCl-NaCl, only the long-wavelength shift of the exciton absorption occurs and the doublet structure undergoes a marked deformation. The results are compared with the X-ray analysis of the mixed samples.