In this paper structural, electric, magnetic, and M€ ossbauer spectroscopy studies were conducted in (x)BiFeO 3-(1-x)BaTiO 3 , 0.9 ! x ! 0.3, solid solutions. X-ray diffraction and Rietveld refinement studies indicated the formation of single-phased materials crystallized in a distorted perovskite structure with the coexistence of rhombohedral and monoclinic symmetries. Room temperature ferroelectric hysteresis loops showed that the electric polarization increases with the increase of the BaTiO 3 content due to the singular structural evolution of the studied solid solutions. All samples presented weak ferromagnetic ordering, which indicates that the BaTiO 3 substitution in the BiFeO 3 matrix released the latent magnetization. M€ ossbauer studies revealed a magnetic spectral signature corresponding to ordered Fe 3þ ions, and a decrease of the magnetic hyperfine magnetic fields with the increase of the BaTiO 3 content. The composition 0.3BiFeO 3-0.7BaTiO 3 presented a spectral signature corresponding to a paramagnetic behavior, which strongly suggests that the observed magnetization in this sample is due to the Ti 3þ ions. V

In this paper, the ferroic properties of polycrystalline LuFe 2 O 4 samples were carefully investigated, and a dissimilar charge ordered state was identified. Strong dielectric dispersion, between 350 K and 225 K; the formation of cluster glass magnetic phases in the same temperature range; and the existence of a ferrimagnetic transition at 230 K indicate the coupling between the ferroelectric and the magnetic orders. Mössbauer spectroscopic investigations, at room temperature, revealed unbalanced contributions of the ferric and ferrous iron ions to the charge ordered state.

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