Non-Stationary Saturation of Inhomogeneously Broadened EPR Lines

Non-stationary saturation of inhomogeneously broadened EPR lines is studied when cross-relaxation has the characteristics of spectral diffusion. A system of generalized kinetic equations is solved in quadratures in this approximation. The result is valid not only when the contribution of the spectral diffusion is negligible or dominant, but also in the intermediate case.