Electron spin resonance of γ-irradiated adipic acid

The radical (CO2H)ĊH(CH2)3(CO2H) has been detected in a γ-irradiated single crystal of adipic acid. It has been calculated from the anisotropy of the spectra on rotation of the crystal that the radicals have almost the same orientation as the undamaged molecules, although the plane of the free radical carbon is twisted approximately 10° from the original plane of the three terminal carbon atoms.