ゼロ熱膨張と鉄磁気性は,広範囲の温度範囲で立方体Sc{1-x) M{-x) F3 (M = Ga, Fe) で表される
Lei Hu1, Jun Chen, Longlong Fan
1Department of Physical Chemistry, University of Science and Technology Beijing , Beijing 100083, China.
Journal of the American Chemical Society
|September 19, 2014
まとめ
研究者らは, (Sc1-xMx) F3材料で300〜900 Kの異例の同位体ゼロ熱膨張 (ZTE) を達成した.このブレークスルーは,高度なアプリケーションのための高温で希少で安定したZTE特性を提供する.
科学分野:
- 材料科学 材料科学とは
- 固体物理 固体物理学
- クリスタログラフィーです.
背景:
- ゼロ熱膨張 (ZTE) は,温度変化で材料が膨張したり収縮したりしない珍しい特性です.
- 最も知られているZTEの材料は,室温以下の温度でのみ,この振る舞いを表しています.
- 高温で同位体ZTEを達成することは,科学的に大きな課題です.
研究 の 目的:
- 拡張された高温範囲で立方体 (Sc1-xMx) F3 (M = Ga, Fe) で非従来の同位体ZTEの発見を報告する.
- このZTE不動産の構造的起源を,局所的およびマクロスコプ的構造分析を通じて調査する.
- これらのZTE材料の多機能特性の可能性を調査する.
主な方法:
- キュービック (Sc1-xMx) F3化合物の合成と特徴付け.
- マクロスコープの結晶学的構造分析のためのX線 difraktion (XRD).
- 局所構造の決定のためのシンクロトロン放射のX線総散乱のペア分布関数分析 (PDF).
主要な成果:
- (Sc0.85Ga0.05Fe0.1) F3で観測された非常規の同位体ZTEは,広範囲の温度範囲 (300~900 K) で,線形CTEは2.34 × 10~7 K~1) である.
- マクロスコープの立方体構造 (Pm3̅m) はXRDによって確認され,局所構造分析はわずかなロムボエドール歪みを明らかにした.
- 地元の構造的歪みは,負の熱膨張の貢献を弱め,ZTEを可能にすると仮定されています.
結論:
- この研究では,高温下での (Sc1-xMx) F3材料における同otropic ZTE が実証され,既存の ZTE 材料よりも著しく進歩しました.
- カチオン置換によって引き起こされる局所的な構造的歪みは,このZTEの特性を達成するための重要なメカニズムとして特定されています.
- これらのZTE材料は,高Tcフェロ磁性および狭間半導体特性を含む多機能性の可能性を示し,将来のアプリケーションの道を開く.
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