MAGNETOOPTICAL PROPERTIES OF NEW MANGANESE OXIDE COMPOUNDS

The investigation of magneto-optical properties of manganese magnetic oxide compounds containing (MnO6)9- and (MnO6)8- octahedral magnetoactive complexes - perovskites, orthomanganites, pyrochlores and ilmenites - and influence of Bi3+ and Pb2+ ions on their magneto-optical activity (MOA) was carried out in the energy range of 1.5-4.5 eV. MOA of investigated compounds was shown to be defined by the transitions in (MnO6)9- and (MnO6)8- complexes, the frequencies of these transitions were determined. The strong increase of MOA at the energies 4-4.5 eV in compounds containing both Bi3+ (or Pb2+) and Mn4+ ions was observed. The enhancement of charge-transfer transitions contribution to MOA due to the admixture of Bi3+(Pb2+)ions' (6p)-wave functions to the molecular orbitals of (MnO6)8- complexes is considered to be the most likely mechanism of this phenomenon.