- Tytuł:
- Phase and Structural Study of Self-Doped La$\text{}_{1-x-y}$Ca$\text{}_{x}$Ø$\text{}_{y}$MnO$\text{}_{3+δ}$
- Autorzy:
-
Figueiras, F.
Araújo, J. P.
Amaral, V. S.
Tavares, P. B.
Lopes, A. B.
Vieira, J. M. - Powiązania:
- https://bibliotekanauki.pl/articles/2037125.pdf
- Data publikacji:
- 2004
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
64.75.+g
81.40.Rs
75.50.-y
72.20.My - Opis:
- To understand the combined effect of divalent ion and A-site vacancy (Ø) self-doping, beyond the binary La$\text{}_{1-x}$MnO$\text{}_{3}$ system, polycrystalline La$\text{}_{1-x-y}$Ca$\text{}_{x}$Ø$\text{}_{y}$MnO$\text{}_{3+δ}$ samples were studied. Samples with Ca substitution and excess Mn in the range x<0.33 and y<0.45, respectively, were prepared by standard solid-state reactions. Structural and phase analysis of the samples were done by X-ray diffraction and transmission electron microscopy. The manganite structure in this composition range includes rhombic and orthorhombic phases. Most samples contain the hausmanite phase (Mn$\text{}_{3}$O$\text{}_{4}$) coexisting with the manganite phase. A small amount of perovskite related AMn$\text{}_{7}$O$\text{}_{12}$ (A=La,Ca) structure near the hausmanite-manganite boundary is also found in samples treated in oxygen atmosphere. The calculated vacancy content accommodated in the manganite phase can be higher than 1/8, the reported limit for La$\text{}_{1-x}$MnO$\text{}_{3}$, which is confirmed in our x=0 sample. For the compositions studied, a ferromagnetic metallic behavior below T$\text{}_{C}$ is found, confirming the stability of the Mn sublattice, and near the optimum stoichiometric ((x=0. 33, y=0) system, a net A-site vacancy content (up to y=0.2) does not degrade the magnetic and electric properties.
- Źródło:
-
Acta Physica Polonica A; 2004, 105, 1-2; 173-182
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł