Magnetic properties of gamma irradiated single crystals of cholesteryl chloride: An EPR study

The cholesteryl chloride compound has been irradiated with Co-60-gamma ray at room temperature. The radical produced by gamma irradiation has been investigated in the range of temperatures 123-450 K for different orientations of the crystal in a magnetic field by electron paramagnetic resonance (EPR). Radiation damage center was attributed to radical CH alpha CH2 beta CH2 gamma. The g factor and hyperfine coupling constants have slight dependency on temperature and evident dependency on the orientation of the magnetic field. Determined g factor and hyperfine coupling constants for the radical CH alpha CH2 beta CH2 gamma, were found to be anisotropic with the average values g(av) = 2.003222,(a(CH alpha))(av) = 16.82G and (a(CH2 beta))(av) = 23.94G measured in all axes and (a(CH2 gamma))(av) = 8G, which was measured only in one axis. (C) 2011 Elsevier Ltd. All rights reserved.