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Updated: May 23, 2026

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Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
ペロブスキートオキシニトリドのサブエクステンシブエントロピーとオープンオーダー
Philip J Camp1, Amparo Fuertes, J Paul Attfield
1School of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, United Kingdom. philip.camp@ed.ac.uk
Journal of the American Chemical Society
|March 27, 2012
まとめ
新しいペロブスキート酸化ニトリド材料は,粒子の大きさに依存する異常な構成エントロピーを表しています. この"オープン・オーダー"現象は,原子規模の乱れと局所的なアニオン・オーダーリングによって引き起こされ,新しい物質構造と特性を生み出す可能性を秘めている.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- クリスタルグラフィーです.
背景:
- ペロブスキート結晶構造は,調節可能な性質を持つ多用途な材料です.
- 構成エントロピーの理解は,物質の行動と安定性を予測するために重要です.
- 原子スケールの乱れと局所的な秩序は,マクロスケールの性質に大きく影響する.
研究 の 目的:
- AMO{3-z) N{-z) オキシニトリドにおける異常なサブエクステンシブな構成エントロピーを予測し,特徴づけること.
- 粒子の大きさ,原子の乱れ,およびエントロピーの間の関係を探求する.
- これらの資料における"オープンオーダー"の性質を分類し,理解する.
主な方法:
- 構成エントロピーの理論的予測.
- 結晶学的秩序と局所的なアニオン順序の分析.
- エントロピーの計算のための一般的なポーリングの氷のルール式の適用.
- オキシニトリドの分類は"オープンオーダー"に基づいています.
主要な成果:
- ペロブスキートオキシニトリド (AMO(3-z) N(z)) の異常なサブエクステンシブな構成エントロピーが予測されている.
- エントロピーは粒子の大きさによって変化し,マクロスコープのサンプルでは原子あたりのゼロに近づきます.
- 局所アニオン順位 (90°回転のM-N-M結合連鎖) を,サブエクステンシブエントロピーの源として特定した.
- これらの材料を,鉄電気ペロフスキートに類似した"オープンオーダー"を示すものとして分類した.
結論:
- 細かい構成エントロピーは,これらの無秩序なペロブスキート酸化ナトリドの重要な特徴である.
- "オープンオーダー"は,それらのユニークな性質を理解するための枠組みを提供します.
- この発見は,新しいオープンオーダーオキシニトリドと分子構造の設計の可能性を示唆しています.
- スピンやチャージなどの他の状態での"オープンオーダー"現象の可能性.
関連する概念動画
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