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Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials
Published on: May 15, 2015
圧力下BH3:分子ディボランモチーフを残す
1Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON, K1A 0R6 Canada.
Journal of the American Chemical Society
|November 23, 2011
まとめ
この研究では,高圧下でのボロン水化物 (BH3)) 構造を理論的に調査した. ディボラン (B(2) H(6) の新しいポリモルフを含む新しい結晶相が発見され,極度の圧力でポリマー鎖が好まれる.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- コンピューティング・ケミストリー
背景:
- ディボラン (B ((2) H ((6)) は,様々な結晶形に存在する.
- ボロン水酸化物の圧力依存構造の進化を理解することは,材料科学にとって極めて重要です.
研究 の 目的:
- 100GPaまでの圧力下で (BH) の分子と結晶の構造を理論的に探求する.
- ボロン水酸化物の新しいポリモルフと圧力安定化相を特定するために.
主な方法:
- 周期密度関数理論 (DFT) の計算を用いた.
- 1 atmから100 GPaの圧力範囲内の結晶構造の理論的研究.
主要な成果:
- 過去のX線 difraktionデータと一致するB(2) H(6) の新しいポリモルフが提案されました.
- メタステーブルなオリゴメリック構造 (トライマー,テトラマー,ヘクサマー) が特定されました.
- ~4 GPaでは,トリマー結晶が最も安定した相になり,その後36 GPa以上のポリマー鎖が続く.
結論:
- ボロン水酸化物の結晶構造は,外圧に対して非常に敏感である.
- ポリマー一次元鎖は,高圧 (36 GPa以上) で最も安定した相であると予測されています.
- この研究は,単純なボロン水酸化物の高圧行動に関する洞察を提供します.
関連する概念動画
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