325ギガパスカルの高密度の水素の新段階の証拠
Philip Dalladay-Simpson1, Ross T Howie1, Eugene Gregoryanz1,2
1School of Physics and Centre for Science at Extreme Conditions, University of Edinburgh, Edinburgh EH9 3JZ, UK.
Nature
|January 8, 2016
まとめ
研究者らは325ギガパスカルを超える極端な圧力で分子水素 (H2) と二酸化水素 (HD) の新しい相 (相V) を観測した. この発見は 密度の高い水素と 潜在的金属状態の 洞察力を与えてくれます
科学分野:
- 高圧物理学
- 材料科学
- 量子化学について
背景:
- 圧縮された原子金属水素の理論的予測は 80年前まで遡ります
- この状態を達成することは 高圧研究における30年ぶりの大きな課題です
- 凝縮物質物理学にとって 極度の圧力下での水素の振る舞いを理解することは 極めて重要です
研究 の 目的:
- 極端な圧縮下での水素と二酸化水素の新しい相を実験的に特定する.
- 325ギガパスカルを超える圧力の水素の物理的性質を記述する.
- 水素相変異に対する同位体の効果を調査する.
主な方法:
- 水素とその同位素を研究するために,高圧ラマン光譜を用いた.
- 実験は,最大388GPaの圧力と最大465Kの温度で実施された.
- 振動のラマン活動と興奮周波数の変化によって,相変化が特定されました.
主要な成果:
- H2とHDで325GPa以上で300Kで新しいフェーズVが観察されました.
- ステージVは,弱まったラーマン活動,振動周波数の圧力依存の変化,低周波刺激の喪失によって特徴付けられます.
- ステージVはD2では観察されず,その代わりにステージIV'は310GPa以上で300Kで変化し,重要な同位体効果を示した.
結論:
- この研究は,水素と二酸化水素のフェーズVに関する最初の実験的証拠を提供する.
- 発見は,相Vの圧力-温度条件を制限し,重要な同位体シフトを強調します.
- フェーズVは,長い間予測された原子的,金属的水素の状態の潜在的前駆者として提案されています.
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