The effects of a variable field of differential frequency on spin-system dynamics

Effects are investigated arising from the superposition of a field with a frequency equal to the difference of the resonance frequencies of two kinds of magnetic centres in a sample. The external variable field is regarded as a sub-system with infinite temperature. The cross-relaxation between the two kinds of magnetic centres is considered as to be sufficiently pronounced. The conditions have been found under which it is possible to observe resonance effects, and their role in the spin-system dynamics is considered.