Analysis of electronic configuration and spin state driving to magnetic properties of La2xBa0.5-xSr0.5-xFe0.9Ni0.1O3-δ (x = 0, 0.25)

Materials possessing composition La 2x Ba 0.5-x Sr 0.5-x Fe 0.9 Ni 0.1 O 3-δ (x = 0, 0.25) have been successfully synthesized through self-combustion technique followed by calcination at 850 °C for 6 h and sintering at 1100 °C for 6 h. It was characterized and analyzed that the cubic structure formed in which Fe and Ni are well suited inside octahedron , and their oxidation state verified to be Fe 3+ /Fe 4+ and Ni 4+ /Ni 5+ . Furthermore, the electronic shell arrangement 3d 4 , 3d 5 , and 3d 6 are a high spin state configuration of both Fe and Ni in Ba 0.5 Sr 0.5 Fe 0.9 Ni 0.1 O 3-δ . When La substituted Ba/Sr in La 0.5 Ba 0.25 Sr 0.25 Fe 0.9 Ni 0.1 O 3-δ , the electronic configuration becomes a low spin state. The ferromagnetic hysteresis curves showed a soft magnetic hysteresis possessing M FM S = 0.05 emu/gr for BSFN. However, LBSFN displays a soft magnetic hysteresis suggested to present multiple magnetic phases or domain structures having M FM S = 0.02 emu/gr. • The La 2x Ba 0.5-x Sr 0.5-x Fe 0.9 Ni 0.1 O 3-δ (x = 0, 0.25) has a cubic structure and is single phase. • The oxidation states of B-site Fe = 3+ and 4+, while Ni = 4+ and 5+. • Fe/Ni exhibits high spin in Ba 0.5 Sr 0.5 Fe 0.9 Ni 0.1 O 3-δ changes to low spin in La 0.5 Ba 0.25 Sr 0.25 Fe 0.9 Ni 0.1 O 3-δ. • The saturated magnetization directly relates to the electron spin state configuration i.e ., unpaired electron.