Magnetic field effect , spin conversion

The magnetic isotope effect (MIE) is one of the most important techniques which have been developed in the course of studies of MFEs on chemical reactions. It is noteworthy that the MIE is a new type of isotope effect This effect comes from the difference in nuclear spin, but not in nuclear mass. According to the HFCM, the S-T conversion of radical pairs depends on the HF interaction between nuclear and electron spins in the component radicals, even in the absence of an external magnetic field. Therefore, it is possible for MIEs to appear in most reactions which show MFEs. 

F.6.3.3. Spin Canting Effects. Mossbauer spectroscopy is appropriate for detecting a noncollinear magnetic structure. If an external field is applied parallel to the y-ray beam, and if all the spins are collinear with this field, then the Am = 0 transitions are forbidden (see Ap.5). The second and fifth lines of a six-line pattern will be absent. Conversely, nonzero second and fifth lines show that a noncollinearity is present in the sample. 

---