ESR STUDIES OF N-ALKANE DIOLS IRRADIATED BY GAMMA-RAYS - IDENTIFICATION OF RADICALS AND MECHANISM OF RADICAL MIGRATION

Free radicals produced by γ-irradiation in n-alkane diol having different molecular chain length are investigated by the ESR method. The dominant free radicals produced are CH2C̊HOH radical and CH2C̊HCH2 radical. The complex radical conformation of CH2C̊HOH radical is determined by computer simulation. Mutual conversion between the two radicals by heating and illumination of u.v. light is observed, which can be written as CH2 C ̊HCH2 ⇄ u.v. ΔHCH2 C ̊HOH The radical conversion from CH2C̊HCH2 to CH2C̊HOH occurs through an intramolecular process and the apparent activation energy obtained for this process is 7 kcal/mol. Kinetics of the radical migration process is discussed on the basis of a potential model for the unpaired electron. © 1979.