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We have carried out soft x -ray absorption spectroscopy to study the electronic structure of ilmenite family, such as MnTiO₃, FeTiO₃, and CoTiO₃ at the soft x -ray beamline, BL23SU, at t he SPring-8. The Ti and M L _2,3 absorption spectra of MTiO₃ (M = Mn, Fe, and Co) show spectra of Ti⁴⁺ and M²⁺ eletron configurations, respectively. Except the Fe L_2,3 spectrum, those spectra were understood within the Oh symmetry around the transition metal ions. The Fe L₃-edge spectrum clearly shows a doublet peak at the L₃ edge, which is attributed to Fe²⁺ state, moreover the very high-resolution the L-edge spectra of transition metals show fine structures. The spectra of those ilmenites are compared.

Eu_1-xSr_xMnO₃ system is one of the perovskite manganites that exhibit the giant magneto resistance effect and the transition from the insulator phase to the metal. Eu_0.6Sr_0.4MnO₃ behaves as a ferromagnetic semiconductor and has an Insulator-Metal (IM) transition induced by external magnetic field, which could be found only in this system among the perovskite manganites group. The mechanism of the transition was investigated by X-ray Magnetic Circular Dichroism (XMCD) at the Mn L_2,3-edges of and the Eu M_4,5 -edges in Eu_0.6Sr_0.4MnO₃.