圧力の下にあるフォスフィンの分解産物:PH2 安定し,超伝導性?
Andrew Shamp1, Tyson Terpstra1, Tiange Bi1
1Department of Chemistry, State University of New York at Buffalo , Buffalo, New York 14260-3000, United States.
Journal of the American Chemical Society
|January 19, 2016
まとめ
高圧リン酸化物 (PHn) は,進化的アルゴリズムと密度関数理論を用いて調査された. 安定した金属PH2相が発見され,臨界温度76Kまでの超伝導性を示した.
科学分野:
- 材料科学
- 凝縮物質物理学
- コンピュータ化学
背景:
- 水素 (PHn) は,高圧の超伝導性を持つ可能性があるため,関心があります.
- 極端な条件下でPHnの相図を理解することは,新しい超伝導体を発見するために不可欠です.
研究 の 目的:
- 高圧 (100〜200 GPa) で最も安定したリン酸水素 (PHn,n=1-6) を予測する.
- 予測された安定した相の超伝導性を調査する.
主な方法:
- 密度関数理論 (DFT) の計算と組み合わせた進化アルゴリズム (EA) を利用した.
- 予測された相に対する計算された動的安定性および超伝導的臨界温度 (Tc).
主要な成果:
- フォスフィン (PH3) は100〜200GPaでは不安定で,PH2とH2の元素相に分解する.
- 5FU-C2/m,I4/mmm,および2FU-C2/mを含む3つの動的に安定した金属PH2相が特定されました.
- 計算された超伝導的臨界温度 (Tc) は,それぞれI4/mmmと2FU-C2/mの相に対して70 Kと76 Kである.
結論:
- 予測された安定したPH2相は,207GPaでのフォスフィンの観測された超伝導性の潜在的な候補である.
- これらの発見は,新しい高圧超伝導体の探求に寄与します.
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