ESR AND ENDOR STUDY OF X-IRRADIATED SINGLE-CRYSTALS OF BETA-ALANINE AT ROOM-TEMPERATURE

Three radicals have been identified in the room temperature ESR spectra of x-irradiated single crystals of β-alanine (N+H 3CH2CH2CO2-). ENDOR spectra from one radical exhibit hyperfine coupling to 1 α-proton (A xx = -33.12, Ayy =-20.68, Azz = -10.50 G) and 2 β-protons [Aiso(Hβ1) = 13.24 G, A iso(Hβ2) = 4.89 G]. From the anisotropic nature of the α-proton coupling it has been determined that these splittings arise from a N+H3CH2CHCO2- radical. It has been shown that this radical is the decay product of the unstable low temperature oxidation product. A second room temperature radical, N+H3CH2CH2C = 0, has been shown to be a decay product of the primary reduction product. A minor room temperature product has been tentatively identified as a CH2-CH2-R radical. © 1979 American Institute of Physics.