Modification of the magnetic properties of $\alpha$-Fe$_{2}$O$_{3}$ powders by ultrasonic processing

Hematite ($\alpha$-Fe$_{2}$O$_{3}$) powders after ultrasonic treatment (UST) in the regime of cavitation in aqueous suspension and in that with an organic component (albumin protein) have been studied by Ms̈sbauer spectroscopy and ferromagnetic resonance techniques. It is established that the UST in aqueous hematite suspensions with albumin results in the formation of a new magnetic phase with parameters coinciding with those of the $\alpha$-Fe metallic phase.