Alternative approach for evalution of Mössbauer spectra of nanostructured ferromagnetic alloys within generalized two-lewel relaxation model

The simplest treatment of the complex $^{57}$Fe Mössbauer absorption spectra of nanostructured Fe-Cu-Nb-B alloys within the recently-developed generalised two-level relaxation model has been successfully performed. This model applied for a system of superparamagnetic particles allows one to take into account the interparticle interaction in a simpler form and to describe qualitatively a specifically asymmetric shape of Mössbauer lines with sharp outer and smeared inward sides when the conventional two-level relaxation model fails. The approach is actually an alternative way in order to evaluate the Mössbauer spectra of nanostructured ferromagnetic alloys without taking into consideration a rather wide and diverse distribution over the particle sizes.