圧力による構造,磁気,および輸送の移行は,2本足の梯子Sr3Fe2O5O5の2本足の梯子で起こります
Takafumi Yamamoto1, Cédric Tassel, Yoji Kobayashi
1Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.
Journal of the American Chemical Society
|March 29, 2011
まとめ
圧力は,構造的,スピン状態,磁気的移行を含む,Sr(3) Fe(2) O(5) に重大な変化を誘導する. これらの発見は,圧力下にある関連鉄基層化合物の一般的な行動を示唆しています.
科学分野:
- 材料科学 材料科学とは
- 凝縮物質物理学 凝縮物質物理学
- 固体化学 固体化学
背景:
- 平方平面のFeO4モチーフを持つ層状鉄化合物は,ユニークな電子および磁気特性を有しています.
- SrFeO(2) は,圧力誘発のスピン状態,断熱器から金属への移行,および磁気移行を示しています.
研究 の 目的:
- 圧力によるSr(3) Fe(2) O(5) の構造,磁気,輸送特性への影響を研究する.
- Sr(3) Fe(2) O(5) が,SrFeO(2) と同様の圧力誘発変遷を示すかどうかを判断する.
- 関連鉄基層化合物のスピン状態移行の一般性を探求する.
主な方法:
- シンクロトロンX線微分法を用いた高圧実験.
- 圧力下での磁気感受性の測定. 圧力下での磁気感受性の測定.
- 圧力下での電気抵抗性の測定. 圧力下での電気抵抗性の測定.
主要な成果:
- Immm から Ammm の対称性への構造的移行は 30 ± 2 GPa で観察されました.
- S=2からS=1へのスピン状態の移行と,反鉄磁性から鉄磁性への移行が34 ± 2GPaで発生しました.
- 断熱器から金属への移行の証拠は,約34 ± 2GPaで観察されました.
結論:
- Sr(3) Fe(2) O(5) は,SrFeO(2) と似たような,圧力による構造的,スピン状態,および磁気的移行を経験する.
- 構造的移行は,スピン状態と磁気移行から独立しているようです.
- これらの結果は,Sr (n+1) Fe (n) O (n+1) シリーズの圧力誘発変異の一般的なメカニズムを示唆しています.
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