ESR and ENDOR measurements on glyclglycine HNO3 x irradiated at 4.2°K

ESR and ENDOR spectroscopy were used to observe the effect of ionizing radiation on single crystals of glycylglycine HNO3 x irradiated at 4.2°K. The paramagnetic species NO32− and NO2 are formed. The N14 hyperfine and quadrupole coupling tensors were determined from the ENDOR spectra, and the g tensors were determined from ESR spectra for both species. A mechanism of NO2 formation is suggested which involves transfer of a proton to NO32− and formation of OH−.