Sr-Pb-Sシステムにおける異常な三位式の有序半導体化合物の理論的予測と実験的確認
Shiqiang Hao1, Li-Dong Zhao, Chang-Qiang Chen
1Department of Materials Science & Engineering, and ‡Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|January 9, 2014
まとめ
CaPbSでは相分離が好ましいが,SrPbS系には,SrPb3S4のような安定した,秩序のある三元化合物が存在する. この研究は,理論と実験を組み合わせて,複雑な半導体合金相関係を理解します.
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
- コンピューティング・マテリアル・サイエンス・サイエンス
背景:
- 端末半導体合金は,相分離を含む複雑な相行動を示すことが多い.
- 相関係を理解することは,望ましい性質を持つ新しい材料を設計する上で極めて重要です.
研究 の 目的:
- 段階分離とCa(x) Pb(1-x) SおよびSr(x) Pb(1-x) Sシステムにおける順序付けの熱力学を調査する.
- 安定した有序三元化合物の存在を予測し,実験的に検証する.
主な方法:
- 密度関数理論 (DFT) 計算.密度関数理論 (DFT) 計算.密度関数理論 (DFT) 計算.密度関数理論 (DFT) 計算.密度関数理論 (DFT) 計算.密度関数理論 (DFT) 計算.密度関数理論 (DFT) 計算.
- クラスター拡大 (CE) 方法.
- モンテカルロ (MC) シミュレーション.
- トランスミッション電子顕微鏡 (TEM).
- バンドギャップ測定. バンドギャップ測定.
主要な成果:
- 大量相分離は,PbS-CaSシステムでは熱力学的に好ましい.
- 安定した有序三元化合物 (SrPb3S4,SrPbS2,Sr3PbS4) は,PbS-SrSシステムで予測されています.
- 実験的検証により,これらの新しい順序化された相の安定性が確認されました.
結論:
- PbS-SrSシステムは,PbS-CaSシステムとは異なり,安定した秩序付けられた相を示す.
- 理論と実験を組み合わせたアプローチは,多成分カルコゲニド系の研究に有効です.
- この研究は,複雑な合金における新しい秩序付けられた化合物の発見の道を開きます.
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