液体から液体への移行と硫黄の臨界点
Laura Henry1, Mohamed Mezouar2, Gaston Garbarino1
1European Synchrotron Radiation Facility (ESRF), Grenoble, France.
Nature
|August 21, 2020
まとめ
研究者らは硫黄の第1次流体-流体移行と臨界点を観察し,水のような物質の流体行動と異常に関する新しい洞察を提供しました.
科学分野:
- 凝縮物質物理学
- 材料科学
- 物理化学
背景:
- リキッド・リキッド・トランジション (LLT) は,単一成分の液体が,第1次相変異を経て,別の液体へと変化することを意味します.
- LLTは様々な物質で予測されているが,実験的に主に超冷却液体で観察され,しばしば同時結晶化によって複雑化している.
- 液体-液体臨界点 (LLCP) は理論化されているが,実験的に確認されていないが,水の異常を説明するために用いられている.
研究 の 目的:
- 硫黄の第1次液体-液体移行 (LLT) と液体-液体臨界点 (LLCP) の直接的な実験的証拠を提供すること.
- 硫黄中のLLTの熱力学的行動と特性を調査する.
主な方法:
- インサイト密度測定の組み合わせ
- X線偏光分析について
- ラマン散射スペクトロスコーピー
主要な成果:
- 低密度の液体相と高密度の液体相の間の急激な密度ジャンプによって特徴づけられる硫黄の第一級LLTの直接的な実験的証拠.
- LLT を確認するペア分布関数の特徴の観察.
- 密度とエントロピーの競合効果に関連した温度との密度ジャンプの非単調な変動を示す.
- 硫黄の液体液体臨界点 (LLCP) の実験的観測
結論:
- この研究は,硫黄における第一級LLTとLLCPの最初の実験的確認を提供します.
- この発見は 液体の複雑な振る舞いを洞察し 水のような他の物質で観察された異常を 説明する可能性があります
- 密度とエントロピーの競合する役割が強調されています.
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