The radiative relaxation of exciton-like creations in KCl-Na single crystal was studied by experimental
methods of luminescent spectroscopy. In the X-ray luminescence spectra of KCl-Na crystals, the emission band with a
maximum at 2.8 eV has been detected for the first time at room temperature.
The effect of multiple amplification of the emission intensity with a maximum at 2.8 eV in KCl-Na crystals is
maximum after hardening (400-7000C), a rise in sodium impurity concentration (for example, 10÷1000 ppm), and when
exposed to uniaxial elastic deformation along crystallographic directions (<100 >, <110>).
At high concentrations of sodium (1000 ppm) in KCl-Na crystals, intense additional emission has been also
detected with a maximum at 3.1 eV, which is typical for paired sodium ions, surrounded by which emissive relaxation of
electronic excitations occurs.
It has been experimentally established that lowering symmetry of KCl-Na lattice by thermoelastic stress during
hardening, by a light cation (Na) during doping, as well as by elastic compression during uniaxial deformation (<100>,
<110>) leads to an increase in the mean free path of the unrelaxed hole before self-trapping. As a result, the probability
of recombination assembly of electron-hole pairs increases with the formation of an exciton-like creation, the emissive
relaxation of which occurs in the field of thermoelastic, local and uniaxial deformation with intense luminescence.