Abstract
The peculiarities of the fine atomic and magnetic structure, magnetic properties and microwave characteristics under Sc-substitution were investigated in Ba(Fe1-xScx)12O19 (x ≤ 0.1) solid solutions. Structural data was obtained using neutron powder diffraction with high resolution on atomic level and was described in the frame of standard P63/mmc Space Group. Almost linear increase of the main lattice parameters and internal stress was explained by the difference in ionic radius of Fe3+ and Sc3+. Magnetic properties were determined by VSM and discussed in terms of Mossbauer studies. The non-linear behavior of the magnetic parameters was explained by the features of Sc3+ ions distribution in the hexaferrite structure and some deviation from strict collinearity in the direction of the magnetic vector. Concentration dependence of coercivity in the concentration range x ≥ 0.05 was explained by rapid frustration of the magnetic structure (destruction of the magnetic long range ordering due to weakening of the intrasublattice exchange interaction in Fe3+-O2--Fe3+ in the first and second coordination spheres). Microwave properties were investigated using a co-axial method in the high frequency range (20–60 GHz). It has been demonstrated that the nature of electromagnetic absorption in Ba(Fe1-xScx)12O19 (x ≤ 0.1) solid solutions is caused by natural ferromagnetic resonance. A good correlation was established between the theoretical calculation of the resonant frequency and the experimental results. It opens broad prospects for practical applications of substituted hexaferrites at higher frequencies.
•Lightly-doped Ba(Fe1-xScx)12O19 (x < 0.1) ceramics were synthesized using solid state reactions.•Strong correlation between Sc3+ concentration and diamagnetic ions distribution was observed.•Control of the high frequency properties of the Ba(Fe1-xScx)12O19 (x < 0.1) ceramics was demonstrated.•Non-linear magnetic and microwave properties was explained by the features of magnetic structure.