Electron spin resonance spectra of irradiated monofluoracetamide

Abstract

The radical trapped in x-irradiated monofluoracetamide is shown to be CHF CONH₂ by electron spin resonance studies. The principal values of the hydrogen hyperfine coupling are -96, -63 and -31 Mc/s and of the fluorine coupling are +530, -11 and -45 Mc/s. The relative signs of the principal couplings were established, using a spectrometer operating at 35 000 Mc/s which is briefly described. The differences in spectra between measurements at 9000 Mc/s and at 35 000 Mc/s are indicated. Finally the couplings are interpreted and shown to be consistent with Hückel parameters for fluorine with (α_F-α_C) = 2·4β_C-F.