On Spin‐Spin Relaxation Effects

Results of different series of observations recently carried out in Leiden on spin‐spin relaxation effects in paramagnetic salts of the iron group are reported and discussed. The character of the frequency‐zero band and the resonance bands in parallel fields have been studied in different Tutton salts, and is found to be in agreement with the present theory. The behavior of the Kronig‐Bouwkamp band in high parallel fields is the same salts is also reasonably well understood; this is not so for Cu(NH4)2Br4·2H2O. The complicated behavior in salts where there is a known tendency to chain formation is also not yet clear.De Vrijer's low‐field third relaxation has been studied in different salts and is confirmed to be a cross‐relaxation phenomenon.