  Radiation defects in barium fluoride single crystals doped with cadmium have
been investigated by luminescence and absorption spectroscopy, as well as by
electron spin resonance spectroscopy. Three types of Cd$^+$ centers differing
by the local environment with the point symmetries O$_h$, C$_3$$_v$ and
C$_2$$_v$ have been identified although in the crystals only the cubic centers
are usually formed. We believe that these features may arise from the
difference in the spacial distribution of the impurities in the crystals.
