The formation of radiation defects in calcium and strontium fluoride single crystals

doped with cadmium or zinc was investigated by luminescence and absorption

spectroscopy, as well as by electron spin resonance spectroscopy. It was found that

x-irradiation could convert divalent impurity ions located at essentially cubic sites

into the univalent state. Three types of Cd+ or Zn+ centers differing by local

environment with point symmetries Oh, C3v and C2v were identified in the crystals.

The formation of the last two results from the interaction between reduced

impurities in the cubic environment and anion vacancies. The latter were intrinsic

radiation defects and were not created by X-irradiation in undoped crystals.

Radiation Defects in CaF2 and SrF2 Crystals Doped with Cadmium or Zinc.

A.V.Egranov, E.A.Radzhabov, V.F.Ivashechkin, M.A.Semenova, I.E.Vasileva:

Journal of Physics - Condensed Matter, 2008, 20[46], 465213