A Simple, Accurate Method to Determine the Effective Value of the Magnetic Induction of the Microwave Field from the Continuous Saturation of EPR Spectra of Fremy’s Salt Solutions. Representative values of T1

A simple protocol to measure the effective value of the circularly polarized magnetic induction of the microwave field is proposed and demonstrated employing continuous-wave saturation of a standard sample of Fremy’s salt measured under specified conditions. The fact that the doubly integrated intensity of first-derivative spectra is invariant with respect to the line shape is used to take into account the non-Lorentzian line shape to study the peak-to-peak intensity or the line width. Corrections for the use of line- rather than point-samples are developed.