- Tytuł:
- Local Structure of Mn in $(La_{1-x}Ho_{x})_{2//3}Ca_{1//3}MnO_{3}$ Studied by X-ray Absorption Fine Structure
- Autorzy:
-
Pietnoczka, A.
Pękała, M.
Bacewicz, R.
Drozd, V.
Fagnard, J.
Vanderbemden, P.
Antonowicz, J.
Zalewski, W. - Powiązania:
- https://bibliotekanauki.pl/articles/1538864.pdf
- Data publikacji:
- 2010-02
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
61.05.cj
75.47.Lx
87.64.kd - Opis:
- Results of X-ray absorption fine structure measurements in manganites $(La_{1-x}Ho_{x})_{2//3}Ca_{1//3}MnO_{3}$ with 0.15 < x < 0.50 are presented. When $LaMnO_{3}$ is doped with a divalent element such as $Ca^{2+}$, substituting for $La^{3+}$, holes are induced in the filled Mn d orbitals. This leads to a strong ferromagnetic coupling between Mn sites. Ca ions in $La_{1-x}Ca_{x}MnO_{3}$ introduce a distortion of the crystal lattice and mixed valence Mn ions ($Mn^{3+}$ and $Mn^{4+}$). On the other hand, in manganites $(La_{1-x}Ho_{x})_{2//3}Ca_{1//3}MnO_{3}$ the substitution of La for Ho causes a lattice distortion and induces a disorder, which reduces a magnetic interaction. The ferromagnetic transition temperature and conductivity decrease very quickly with increasing x. The magnetic and transport properties of compounds depend on the local atomic structure around Mn ions. The information on the bond lengths and Debye-Waller factor are obtained from the extended X-ray absorption fine structure (EXAFS) data analysis. The charge state of Mn is determined from the position of the absorption edge in X-ray absorption near edge structure (XANES) data. XAFS results are in good agreement with magnetic characteristics of the studied materials.
- Źródło:
-
Acta Physica Polonica A; 2010, 117, 2; 281-285
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł