Structural and Magnetic Properties Control of Рг0,7 Вао.зМnOз with Sr-Doping

Аннотация

Structural and magnetic properties of Sr-doped Рг0,7 Вао.зМnOз polycrystallines prepared by solid state reaction are presented. Samples were in monoclinic structure P2\/n without structural phase transition when Ba was gradually replaced by Sr. Parameters a, b, and с of a unit cell monotonously decrease with increasing Sr content, while p angle has increased from 89.981° to 90.007°. The X-ray absorption spectra show the co-existence of Mn3+ and Mn4+ ions in materials and the number of Mn4+ ions increases in the presence of Sr. The thermal magnetization data indicate that the Curie temperature shifts toward room temperature from 190, 210, 232 to 267 К with increasing Sr content x from 0 to 0.3.