Alkali hyperfine coupling constant in biphenylene alkali metal ion pairs

Abstract

The ion pairs formed by the biphenylene radical anion with all the alkali metal ions have been investigated by e.s.r. spectroscopy.

A complete analysis of the linewidth variation within the ¹³³Cs multiplet and the ¹³C satellites leads to a positive sign for the ¹³³Cs hyperfine coupling. For the other alkali nuclei a positive coupling is suggested on the basis of the temperature variation of the hyperfine splitting.

For Na biphenylene the experimental data are compared with theoretical calculations of the alkali metal spin densities.