Analysis of the NMR and Double-Resonance Spectra of the Isomers of N2F2

The assignment of F19 NMR spectra of the two isomers of N2F2 is consistent with the assumption of trans and cis 1,2-difluorodiazine structures for these molecules. The qualitative features of the F19—{N14} double-resonance spectra, and a comparison of the F19 NMR spectra at 56.4 and 40.0 Mc/sec strongly favor a cis structure over a 1,1-difluorodiazine structure for the more reactive isomer. A comparison of the indirect N–F coupling constants for the two isomers indicates that the FNN angles are probably quite different for cis and trans N2F2.