Influence of Cr2O3 nanoparticles on NMR relaxation times near Néel temperature

Antiferromagnetic particles can significantly influence nuclear magnetic resonance (NMR) relaxation times through mechanisms such as uncompensated surface spins, spin canting, and

localized magnetic fluctuations. In this research, we examined chromium(III) oxide (Cr₂O₃) nanoparticles, an antiferromagnet with a Néel temperature (TN) of 307K (34°C) in its bulk form. Our study focused on two particle sizes, 60 nm and 18 nm, analyzing changes in magnetization near TN across different fields. We explored how these changes are reflected in NMR results at various fields for both sizes, and in MRI results at 64 mT, particularly observing changes near the Néel temperature.