This work presents influences of the Mn doping on structure, optical and magnetic properties of BaTi_1-xMn_xO₃ (x = 0.0-0.12) prepared by conventional solid-state reaction. Detailed analyses of XRD patterns and Raman scattering spectra indicate a structure transformation from tetragonal-to-hexagonal in the BaTiO₃ doped with Mn taking place at a threshold concentration of x_c » 0.01. The increase of Mn-doping content in BaTi_1-xMn_xO₃ created defect levels into forbidden gap that broadened the absorption band and depressed the photoluminescence emission of material in the visible light. Magnetic data recorded reveal that all the samples exhibite room-temperature ferromagnetic order, and there is a phase separation in magnetism as varying x values. Particularly, the samples with x = 0.5-0.7 exhibits a coexistence of two ferromagnetic phases with different coercivities, associated with tetragonal and hexagonal BaTiO₃ structures. The nature of ferromagnetism was comprehensively explained by means of the magnetic exchange interactions between Mn³⁺ and Mn⁴⁺ ions in a lattice structure of the phases competition.

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