Experimental Studies of Power-Saturated Spin Modes of Nitroxides in Liquids 1

In recent years, the theory of the effect of saturation of EPR spectra of free radicals undergoing spin exchange has been extended to spin exchange frequencies where “peculiar” behavior occurs. In a paper by Salikhov (Appl. Magn. Reson. (2021) 52:1063–1091), analytic expressions were developed that predict the dependence of measurable EPR parameters on the exchange frequencies and the microwave field strength. This work is an experimental test of that theory where, in principle, there are no adjustable parameters.