Free radicals in γ-irradiated disodium succinate. Part 2. Triclinic crystals

Abstract

Electron spin resonance (e.s.r.) spectra and radiation processes in γ-irradiated triclinic crystals of disodium succinate are more complex than those observed in monoclinic crystals. At 77°K, three species coexist, −O2CCH2CH2ĊO22− (1), a distorted conformation of the radical −O2C(ĊHCH2)*CO2−(2), and an unidentified radical X. On warming to room temperature, 1 and X disappear, while 2 changes to a more stable conformation −O2CĊHCH2CO2− (3). In addition the species CO2− (4), and −O2CĊHCH3 (5) are produced. On further warming to 40 °C, species 4 disappears while at the same time species 3 increases in intensity. Radical 5 remains unaffected. Possible mechanism and comparisons with monoclinic crystals are discussed.