Comparative studies of ferroelectric and magnetic phase transitions in Pb(Fe1/2Nb1/2)O3-PbMO3 (M-Ti, Zr) multiferroic solid solutions

Some peculiar features of magnetic x,T-phase diagram of (1-x)PbFe1/2Nb1/2O3- xPbTiO3 system at x ≈ 0.1 have been ascribed previously to the change of the lattice symmetry from rhombohedral to tetragonal or to the decrease of the lattice parameter with x. We carried out structural, dielectric, magnetization, and Mossbauer studies of (1-x)PbFe1/2Nb1/2O3-xPbZrO3 system, where the symmetry remains rhombohedral, while the lattice parameter increases with x. However, the magnetic x,T-phase diagram of (1-x)PbFe1/2Nb1/2O3-xPbZrO3 appeared to be very similar to that of (1-x) PbFe1/2Nb1/2O3-xPbTiO3. Anomalies of composition dependence of magnetic phase transition temperatures at x ≈ 0.1 are supposed …