Combined hyperfme interaction

We have introdueed the RP spin Hamiltonian, the mechanism of nuclear spin seleetive intersystem erossing, and the reaction scheme for RPs has been explained. We now possess all the tools we need to explain qualitatively how nuclear spin polarization arises and manifests itself in a CIDNP speetrum. The RPM may appear in a CIDNP spectrum as a net effect, a multiplet effect, or a combination of both. The net effeet is observed when the g factor difference between radieals and S) radieal pair is large eompared with the hyperfme interaction. The simplest example involves a RP with just one hyperfme interaetion, as shown in figure Bl.16.5. In this example we will set the following conditions (1) the RP is initially a singlet ... 

K. E. R. England, C. M. B. Henderson, J. Chamock, and D. J. Vaughan, "Investigation of Fe Structural Environments in Leucite Type Framework Silicates Using a Combination of Mdssbauer and X-ray Absorption Spectroscopies," Hyperfme Interact., 91,709-14 (1994). 

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