The electron spin resonance spectra of radical-ions derived from biphenylene and binaphthylene

Abstract
The electron spin resonance spectra of the biphenylene cation and anion and the binaphthylene anion are described. The proton hyperfine splitting constants for the ions derived from biphenylene are in good agreement with predictions based on molecular orbital calculations. The results for the binaphthylene anion are less satisfactory. Additional 13C hyperfine splittings observed in the spectrum of the biphenylene anion are satisfactorily accounted for by the recent theory of Karplus and Fraenkel.