부산대학교 도서관

Phase pure cobalt ferrite of spinel structure (CoFe2O4) is experimentally synthesized using bulk powder processing methods and characterized using neutron diffraction methods to quantify cation site occupation, magnetic moment, and magnetic ordering as a function of temperature. Experimentally determined properties were compared with values calculated from first principles obtained using density functional theory. The obtained results show excellent agreement, and the combination of experimental and theoretical methods enables the unambiguous extraction of exchange bond energies between A–A, B–B, and A–B sites in the spinel structure. The agreement between the theoretical predictions and experimental results exceeds that of traditional empirical fitting methods using average magnetization as a function of temperature. The moment of the B site cation was experimentally estimated to be canted by approximately 2.4° at 4 K. The proposed methods offer an opportunity to further explore spinel ferrite systems for a deeper understanding of bonding and exchange interactions within these complex and interesting ferrimagnetic systems.