Magnetic phase transitions in Ln 1–x Sr x Co0.5Mn0.5O3 (Ln = La, Pr, Nd, and Eu)

Autor: M. V. Bushinskii, V. M. Dobryanskii, O. S. Mantytskaya, I. O. Troyanchuk, N. V. Tereshko, A. N. Chobot, V. V. Sikolenko, E. A. Efimova
Rok vydání: 2017
Předmět:
Zdroj: Physics of the Solid State. 59:728-732
ISSN: 1090-6460
1063-7834
DOI: 10.1134/s1063783417040291
Popis: The system of La1–xSrxCo0.5Mn0.5O3 solid solutions have been studied by neutron diffraction and the measurement of the magnetization. The composition with x = 0 has the monoclinic structure (space group P21/n); the compositions with 0.15 ≤ x ≤ 0.6 are rhombohedral (R\(\bar 3\)c), and the composition with x = 0.75 is cubic (Pm\(\bar 3\)m). All the compositions with x ≤ 0.75 are shown to contain a ferromagnetic component. The stoichiometric composition with x = 0.5 undergoes a sharp ferrromagnet–paramagnet transition at 240 K; however, no coherent magnetic contribution to the neutron diffraction has been detected. The magnetic data are interpreted, assuming that the ferromagnetism at x ≤ 0.15 is due to positive superexchange Co2+–O–Mn4+ interaction, while, at x ≥ 0.25, the superexchange interaction between ions Co3+ in a high-spin state and ions Mn4+ is responsible for the ferromagnetic component.
Databáze: OpenAIRE