Tuning the Magnetic Order in Sc-Substituted Barium Hexaferrites

Polycrystalline BaFe12-<italic>x</italic>Sc<italic>x</italic>O19 hexaferrites (<italic>x</italic> 0.1, 0.6, and 1.2), produced using ceramic technology, have hexagonal structure with space group (P63mmc) as determined by neutron powder diffraction. Magnetic properties were analyzed by vibrating sample magnetometry and Mssbauer spectroscopy. Tuning the magnetic parameters by Sc substitution is associated with several factors: first, ordering the Sc-3 ions in positions 2<italic>b</italic> and 4<italic>f</italic>2 and the cation vacancies at the boundary of the spinel and hexagonal blocks; second, transfer of spin density from Fe ions localized at position 12<italic>k</italic> to 3<italic>d</italic> orbitals of Sc-3 ions; third, weakening the indirect exchange interactions between 2<italic>b</italic>, 4<italic>f</italic>2, and 12<italic>k</italic> sublattices; and finally, presence of a noncollinear magnetic order for Sc concentration <italic>x</italic> above 0.6.