イテルビウム:高圧で面中心の立方体から体中心の立方体構造への移行
Science (New York, N.Y.)
|January 11, 1963
まとめ
高圧によりイテルビウム金属が変形する.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
背景:
- イテルビウム (Yb) は,ユニークな電子特性を有する希土金属です.
- 極端な条件下にある金属の相変異は,物質の振る舞いを理解する上で極めて重要です.
研究 の 目的:
- 高圧がイテルビウム金属の結晶構造に及ぼす影響を調査する.
- 段階変換中の原子体積とマクロスコープ体積の変化を定量化するために.
主な方法:
- イテルビウム金属を25°Cで4万大気圧の圧力にさらした.
- X線微分法 (明示的に述べられていないが暗示されている) を用いて構造変化を分析する.
- 原子とマクロスコープの体積の変化を測定する.
主要な成果:
- イテルビウム金属で相変化が発生した.
- 結晶構造は,顔中心の立方体 (FCC) から体中心の立方体 (BCC) に変化した.
- 原子半径は1.82から1.75 Åに減少し,原子体積は11%減少した.
- マクロスコープの体積は3.2%減少した.
結論:
- 極度の圧力により,イテルビウムの構造と体積が大きく変化します.
- イテルビウムにおけるFCCからBCCへの移行は,実質的な原子圧縮に伴います.
- これらの高圧現象を理解することは,材料科学アプリケーションの鍵です.
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