Unstable intermediates. Part LXXV. Electron spin resonance studies of the effect of environment upon the hyperfine parameters for PO32– and NO32–
Abstract
The radicals PO32– and NO32–, formed in a variety of solids on exposure to high-energy radiation, have hyperfine parameters (31P and 14N) which are strongly dependent upon the nature of the host crystal. The results, which have been analysed in terms of s- and p-orbital contributions, show that, for PO32–, the spin-density is strongly dependent upon the medium, with the p to s ratio increasing slightly as the spin-density on phosphorus falls. However, the spin-density on 14N in NO32– is almost independent of the environment, but the p to s ratio is very sensitive to it. These results are discussed in terms of the trends observed within the isoelectronic families of these two radicals.