EPR investigation of irradiated strontium and zinc acetate single crystals

Abstract

X-ray irradiation of strontium acetate hemihydrate produces CH3C022- and not the methyl radical as in other acetates. At higher temperatures this spectrum is replaced with two magnetically distinct ·CH2 CQ2- radicals. In the presence of the propionate. ion, further reaction proceeds at about -30°C to yield one rotamer of one magnetically distinct CHaCHCO,- radical. The ratio of propionate/acetate damage at room temperature is found to be 700: 1in strontium acetate, indicating some mechanism for the delocalization of the damage. This same reaction with a substituted propionate ion occurs in zinc acetate with a ratio of 20: 1. The coupling tensors for all species are presented.