Structural and electron paramagnetic resonance of Fe³⁺ Sm³⁺ co-doped BaTiO₃

Structural and electron paramagnetic resonance (EPR) of Ba_(1-x)Sm_xFe_yTi_(1-y)O₃ (BSFT) with y=l% and x=0.25,0.50, 0.75% materials were prepared by sol-gel combustion method. The room temperature powder X-ray diffraction confirms the formation of single-phase perovskite (ABO3) structure with tetragonal symmetry (P4mm) for all the prepared samples. The EPR spectra of BSFT samples shows a broad signal and the giromagnetic constant values for Fe³⁺, Sm³⁺ are 1.999 and 1.998 respectively. The broadness of EPR spectra confirms the paramagnetic nature and strong dipolar-dipolar interactions of prepared BSFT ceramics. EPR spectra oxidation state as Fe³⁺ ion, along with the paramagnetic center of Ti³⁺ ion and surface defects, exhibited in the samples. The optical band gap values calculated from UV-spectra shows an increasing trend in bandgap values with decrease in crystallite size is due to Sm³⁺ ion CO-doping concentrations in Ba(_1-x)Fe_0.01Ti_0.99O₃ (BFT).