Abstract :
Electron paramagnetic resonance (EPR) and static magnetization data on manganese substituted (up to 3 mol%) strontium tintanate (Mn:SrTiO3) samples are presented. Four EPR signals are observed from different Mn4+ and Mn2+ sites. The behavior of their intensity vs. temperature is discussed. It suggests the presence of antiferromagnetic interactions in heavily Mn doped grain boundaries. X-ray diffraction analysis shows two coexisting perovskite-type phases, whose abundance depends on the Mn content.
