A-サイトとB-サイトのチャージオーダーリングは,s-dレベル制御されたペロブスキート酸化物PbCoO3
Yuki Sakai1, Junye Yang2, Runze Yu3
1Kanagawa Academy of Science and Technology , KSP, 3-2-1 Sakado, Takatsu-ku, Kawasaki City, Kanagawa 213-0012, Japan.
Journal of the American Chemical Society
|February 28, 2017
まとめ
合成されたペロブスキートPbCoO3は,鉛とコバルトイオンの両方においてユニークな電荷配列を示し,Pb2+Pb4+3Co2+2Co3+2O12四重ペロブスキート構造を形成する. この複雑な電荷分布は,様々な高度な材料特性技術によって確認されました.
科学分野:
- 材料科学
- 固体化学
- 凝縮物質物理学
背景:
- ペロブスキート酸化物 (ABO3) は,多様な電子および磁気特性で知られています.
- ペロフスキットでのチャージオーダリングは,新しい機能につながります.
- 複雑なバレンスの状態を理解することは 材料の設計に不可欠です
研究 の 目的:
- 高圧で合成されたペロブスキートPbCoO3の電荷分布を調査する.
- 充電順の四重ペロブスキート構造の形成を解明する.
- これらの独特のバレンスの状態の安定化メカニズムを探求する.
主な方法:
- 高圧合成 (12GPa)
- 密度関数理論 (DFT) の計算
- 高度な構造およびスペクトル解析:電子 difraktion (ED),シンクロトロンX線 difraktion (SXRD),ニュートロン粉 difraktion (NPD),硬質X線光放射スペクトル検査 (HAXPES),軟質X線吸収スペクトル検査 (XAS).
- 物理的性質の測定:特異的熱,磁気,電気的性質
主要な成果:
- Pb2+Pb4+3Co2+2Co3+2O12という 異常な電荷分布を発見しました
- ペロブスキート構造のA (Pb) 部位とB (Co) 部位の両方でのチャージオーダーの証拠
- 四重ペロブスキート構造の確認
- Pb6sと移行金属の3d軌道エネルギーを調節すると,Pb3.5+Co2.5+O3の平均値が安定することを実証した.
結論:
- 高圧下でのペロブスキートPbCoO3は,複雑な電荷順序を示し,新しい四重ペロブスキート構造を生み出します.
- 観測された電荷の順序は物質の性質に大きく影響する.
- 電子軌道エネルギーを調節することで,ペロブスキットの複雑なバレンスの状態を制御し,安定させることができます.
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