Radiation damage studies of CrO42−-doped alums

Radiation damage studies on NH4Al(SO4)2⋅12H2O and KAl(SO4)2⋅12H2O single crystals doped with chromate centers are presented. Similar studies on undoped alums are also reported for comparison. EPR and optical absorption results are correlated to identify and characterize the species produced on x irradiation of these crystals. Formation of CrO43− ions seems to be the most interesting feature in the doped crystals. The radicals associated with host lattices are identified as SO3−, O3−, and SO2−. The effect of impurity on the stabilization of these radicals is discussed. Results regarding the growth and decay of all these centers during irradiation and the possible kinetics of radiolysis are presented.