ハイパーバレンシーを回避:単純に置換されたBrF3およびBrF5分子. ブロミン水素フッ化物HBrF2およびHBrF4の構造,熱化学,および電子相性
Qianshu Li1, Liangfa Gong, Yaoming Xie
1Department of Chemistry, School of Science, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
Journal of the American Chemical Society
|November 13, 2004
まとめ
この研究では,高価構造ではなく,ブロミン水素フッ化物複合体が,HBrFの最も安定した形態であることを明らかにしました (n) (n=2,4). これらの複合体は水素結合を特徴とし,関連するハロゲン系と比較できる重要な電子相性を持っています.
科学分野:
- コンピューティング・ケミストリー
- 量子化学とは,量子化学である.
- 無機化学 無機化学とは
背景:
- 密度関数理論 (DFT) とハイブリッドのハートリー・フォック/DFT方法は,分子特性の予測に極めて重要です.
- ハロゲン化合物の安定性と反応性を理解することは,化学において重要である.
研究 の 目的:
- ブロミン水素フッ化物HBrF (n) とそのアニオン (n=2,4) の分子構造,熱化学,電子相性について調べる.
- 最も安定した構成を決定し,ハイパーバレンタル構造か複合構造が優位かどうかを特定します.
主な方法:
- 5つのDFTとハイブリッドのHartree-Fock/DFT方法を採用しました.
- 拡散関数を持つ二重ゼータ加極化 (DZP++) ベースセットを使用した.
- 計算された分子構造,熱化学,および電子相性.
主要な成果:
- HBrF (n) /HBrF (n) (n=2,4) のグローバル・ミニマは,高値構造ではなく,水素結合複合体であると予測されています.
- 高解離エネルギーを持つ分子であるHFへの好ましい解離は,これらの複合体の形成を促します.
- BHLYP.を使用した3.69 eVのHBrF(2) と4.38 eVのHBrF(4) のアディアバティック電子相性 (EA(ad)) を計算した.
結論:
- HBrF (n) の高価構造は,水素結合複合体と比較してエネルギー的に不利である.
- これらの複合体の安定性は,HFの強い解離エネルギーによって影響を受けます.
- 計算された電子相性度は,関連する Br,Cl,Fを含むシステムの相性と比較できます.
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