場所と酸化状態の特異性により,ペロブスキートルテナートにおける寸法制御が得られます
Job T Rijssenbeek1, Sylvie Malo, Vincent Caignaert
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|March 7, 2002
まとめ
新しいペロブスキートルテネート,Sr(3) CaRu(2) O(9) を合成し,特徴づけました. この素材は独特の層構造を示し,3Dと層の相の間で可逆的に変換することができ,構造的多用途性を示しています.
科学分野:
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
- クリスタルグラフィーです.
背景:
- ペロブスキートルテナートは,その多様な電子および磁気特性により興味を惹きます.
- ペロブスキットのB位順序は,構造的および物理的な特徴に影響します.
研究 の 目的:
- 新しい2:1B位のオーダーペロブスキートルテネート,Sr(3) CaRu(2) O(9) の結晶構造を合成し,決定する.
- この新しい材料の構造変化と化学的多用途性を調査する.
主な方法:
- 粉末のX線微分光差法によるX線微分光差法
- 中性子 difrractionによって,中性子 difrractionによって,中性子 difrractionによって,中性子 difrractionによって,中性子 difrractionによって,中性子 difrractionによって,中性子 difrractionによって
- 電子 difrractionによる電子 difrractionによる電子 difrractionによる電子 difrractionによる電子 difrractionによる
- 化学的還元と酸化による.
主要な成果:
- Sr ((3) CaRu ((2) O ((9)) を合成し,その構造を決定し,CaO ((6) とRuO ((6) 層のユニークな積み重ねを明らかにしました.
- この化合物は,偽立方方向に沿った [-Ru-Ru-Ca-] 繰り返し単位を特徴としています.
- Sr(3) CaRu(2) O(9) は,ラドルズデン-ポッパー相 (Sr(1.5) Ca(0.5) RuO(4) に還元され,その後,元の構造に再酸化することができます.
結論:
- Sr(3) CaRu(2) O(9) は,d(3) の電子を持つRu(V) を組み込み,ペロブスキートルテネートの新しい構造型を表しています.
- 3D構造と層構造の間の可逆変換は,Sr-Ca-Ru-Oシステムによって提供される重要な構造的汎用性を強調しています.
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