トングステン・ブロンズ型Relaxor PbBiNb5O15における異常な強い不均衡調節
Kun Lin, Zhengyang Zhou1, Laijun Liu2
1College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.
Journal of the American Chemical Society
|October 17, 2015
まとめ
研究者は鉛とビスムスの化合物を 鉄電性物について調べた. PbBiNb5O15は 強い局所的偏分と 独特の構造的調節を示し 電気機械装置の可能性を示唆しています
科学分野:
- 材料科学
- 固体化学
- クリスタルグラフィー
背景:
- 鉛とビスムートベースのペロブスキート酸化物は,立体化学的に活性な単体ペア電子による電極化で知られています.
- 関連系におけるこの効果の存在は,材料発見の関心分野であり続けています.
研究 の 目的:
- TTBフレームワークで新しい混合PbとBiAサイトの極性化合物,PbBiNb5O15を設計し合成する.
- 合成材料の構造と鉄電性の性質を調査する.
主な方法:
- TTBフレームワークでPbBiNb5O15を合成する.
- 構造的変調を観察するために電子 difraktion.
- 高解像度のシンクロトロン放射と (3+1) D超空間群の枠組み内の異常分散X線微分は,構造変調を解き,PbをBiから区別する.
主要な成果:
- PbBiNb5O15は合成され,弱いマクロスコープのフェロ電気性を持つリラックス剤として特定されましたが,強い局所的分極化があります.
- 非常に発達した構造的調節を示す,不均衡な衛星反射の異常な5つの順序が観察されました.
- 変調は解明され,単対駆動のPb2+-Bi3+) 順序から発生し,長距離の平面内偏化を抑制する.
結論:
- この研究は,混合Pb-Biシステムにおける単一のペア駆動のオーダーリングが,複雑な構造的調節とリラクサー・フェロ電気的行動につながる可能性があることを示しています.
- PbBiNb5O15は,室温への移行と適度な介電特性により,電機装置の用途に適した性質を示している.
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