Chemical Control of the Néel Temperature and Magnetic Anisotropy in the Brownmillerites Ca2Fe2–x Mn x O5, x = 0.10–0.25

Brownmillerite oxides with the composition Ca₂Fe_2-xMn_xO₅ had been investigated previously for the limited range x = 0.5 to 1.0. Mn³⁺ preferentially occupies the octahedral site. This substitution has a strong impact on the magnetic properties as the magnetic ordering temperature, T_N, is suppressed from 730 K for x = 0.0 to 465 K for x = 0.5 and the magnetic structure changes from G_x (x = 0.0) to G_y (x = 0.5-1.00). In this study, the …