Crystal and magnetic structures, magnetic and ferroelectric properties of strontium ferrite partially substituted with in ions

The influence of temperature factor to crystal structure as well as magnetic and electric properties of strontium hexaferrite partially substituted with diamagnetic indium ions has been investigated. Ferroelectric properties have been found out in SrFe11.9In0.1O19 compound that contradicts to conventional opinion, which describe its crystal structure within the framework of centrosymmetric space group P63/mmc (No. 194). For determination features of the crystal structure, which are responsible for ferroelectric properties of strontium hexaferrite, have been carried out neutron diffraction measurements with high resolution in temperature range from 1.5 to 740 K. The analysis of hexaferrite structure has been executed within the framework both centrosymmetric and non-centrosymmetric space group. Values of coefficients of magneto crystalline anisotropy at 5 and 300 K and influence of ambient temperature to linear size of magnetic regions have been determined from magnetic measurements. •Spontaneous polarization has been found in polycrystalline SrFe11.9In0.1O19 strontium ferrite at room temperature.•Crystal structure of strontium hexaferrite has been refined in the framework of non-centrosymmetric space group.•Existence of spontaneous polarization in M-type hexaferrite has been explained by different distortions of oxygen polyhedra.