いくつかのLa(2/3-x) Li 3xTiO3酸化物の結晶構造と微細構造:複雑な材料を研究するために,電子 difraktionと顕微鏡とシンクロトロンX線 difraktionの補完的な使用の例
Susana García-Martín1, Miguel A Alario-Franco, Helmut Ehrenberg
1Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense, 28040- Madrid, Spain.
Journal of the American Chemical Society
|March 18, 2004
まとめ
研究者はLa2/3-x) Li3x) TiO3酸化物を研究し,傾斜したTiO6八面を持つペロブスキートに関連する構造を明らかにしました. この研究は,結晶構造のモデルを精製し,これらの材料の複雑な微細構造を説明します.
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
- クリスタログラフィーです.
背景:
- La(2/3-x) Li(3x) TiO3酸化物は,応用の可能性のある複雑な材料です.
- 彼らの結晶構造と微細構造を理解することは,性質の予測に不可欠です.
研究 の 目的:
- 酸化物La(2/3-x) Li(3x) TiO3の結晶構造と微細構造を解明する.
- 観察された複雑さを考慮した洗練された構造モデルを提案する.
主な方法:
- 選択領域電子 difraktion (SAED) (選択領域電子 difraktion) (SAED) とは,選択された領域の電子 difraktion (SAED) を意味する.
- 高解像度トランスミッション電子顕微鏡 (HRTEM)
- 粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは,粉末シンクロトロンX線 difrractionは
主要な成果:
- TiO6八面体の傾きから生じた,対角単位細胞 (√2ap x √2ap x 2ap) を有するペロフスキート関連構造が特定されました.
- La,Li ions,および空白のオーダーリングとTi ionの移動が決定されました.
- ドメインのサイズ/形状と,ストレインや組成の変動のような拡張欠陥が特徴付けられました.
結論:
- この研究は,La2/3-x) Li3x) TiO3酸化物の洗練された構造モデルを提供します.
- 提案されたモデルは,観察された複雑な微細構造を成功裏に統合しています.
- 欠陥の詳細な特徴は,材料の特性についての洞察を提供します.
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