Mössbauer evaluation of the interparticle magnetic Interactions within the magnetic hyperthermia beads

Mössbauer spectroscopy was used for direct experimental measurement of the Néel barrier height for magnetization reversal in ensembles of interacting γ-Fe2O3 nanoparticles. As the barrier height is proportional to the size of the magnetic cluster, these measurements enable an evaluation of the relative sizes of the magnetically coupled clusters that are formed during the manufacture of the magnetic hyperthermia beads. For the hyperthermia beads, which were synthesized and studied in the work, an increase in the size of the magnetically coupled cluster corresponds to a reduction of the specific loss power.