Evaluation of Lattice Site and Valence of Mn and Fe in Polycrystalline PbTiO3 by Electron Spin Resonance and Thermogravimetry

The oxides of Mn and Fe or combinations of La₂O₃ with these oxides were incorporated into PbTiO₃ under defined thermodynamic conditions. The substitution reaction of these additives was examined gravimetrically. At low partial pressures of O₂ and PbO vapor, Mn²⁺ and Fe²⁺ are formed at the A sites, and Mn³⁺ and Fe³⁺ enter both A and B sites. At higher partial pressures of PbO, Mn⁴⁺ is most probably formed at the B sites.
The Mn²⁺, Mn⁴⁺, and Fe³⁺ were determined by ESR.