Valence-state mixing and separation in SmBaFe2O5+w

被引：60

作者：

Linden, J ^{[1
]}

Karen, P

Kjekshus, A

Miettinen, J

Pietari, T

Karppinen, M

机构：

[1] Abo Akad Univ, Dept Phys, FIN-20500 Turku, Finland

[2] Univ Oslo, Dept Chem, N-0315 Oslo, Norway

[3] Helsinki Univ Technol, Dept Tech Phys, FIN-02015 Espoo, Finland

[4] Helsinki Univ Technol, Inorgan & Analyt Chem Lab, FIN-02150 Espoo, Finland

来源：

PHYSICAL REVIEW B | 1999年 / 60卷 / 22期

关键词：

D O I：

10.1103/PhysRevB.60.15251

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

A mixed-valence state, formally denoted as Fe2.5+, is observed in the 300 K Mossbauer spectra of the most reduced samples of SmBaFe2O5 + w. Upon cooling below:the Verwey-type transition temperature (T-V approximate to 200 K), the component assigned to Fe2.5+ separates into a high-spin Fe3+ state and an Fe2+ state with an unusually low internal field. The separation of the mixed-valence state;at T-V is also confirmed by magnetic susceptibility measurements and differential scanning calorimetry. A model is proposed which accounts for the variation of the amount of the mixed-valence state with the oxygen content parameter w. [S0163-1829(99)00446-4].

引用

页码：15251 / 15260

页数：10

共 23 条

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