Features of crystal structure and dual ferroic properties of BaFe12-xMexO19 (Me=In3+ and Ga3+; x = 0.1-1.2)

The investigation of crystal and magnetic structures of BaFe12-xMexO19 (Me=In3+ and Ga3+; x = 0.1-1.2) solid solutions has been carried out by time-of-flight neutron diffraction method. It was determined the influence of diamagnetic In and Ga ions to unit cell volume of partially substituted barium ferrites. The electric field-induced polarization was observed in the BaFe11.9Me0.1O19 (Me = In and Ga) solid solutions at room temperature. The refinement of crystal structure of barium ferrites has been carried out in frameworks of two possible space group: centrosymmetric P63/mmc (No. 194) and non- centrosymmetric P63mc (No. 186) that allowed to reveal reasons of appearance of nonzero dipole electric moment. For description of magnetic structure of BaFe12-xMexO19 (Me = In and Ga; x = 0.1-1.2) solid solutions was used the Gorter's model where magnetic moments of iron ions are oriented along the hexagonal axis that is the axis of easy magnetization.