フェニロキセニウムイオン:イソエレクトロニックフェニルニートレンよりもフェニロキセニウムイオンに似ている?
Patrick J Hanway1, Arthur H Winter
1Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
Journal of the American Chemical Society
|March 10, 2011
まとめ
フェニロキセニウムイオンとは
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.
- 理論化学 理論化学について
背景:
- フェニロキセニウムイオン (Ph-O(+)) はフェニルニトレンに同電子である.
- それらの電子状態を理解することは,化学反応性にとって極めて重要です.
- フェノキシラジカルに対する紫外線光電子スペクトロスコピーの帯の以前の割り当ては,改訂を必要とするかもしれません.
研究 の 目的:
- フェニロキセニウムイオンの電子状態とエネルギーを計算する.
- フェニロキセニウムイオンの電子構造をフェニルニトロネと比較する.
- フェニロキセニウムイオンの電子状態に対する置換物の影響を調査する.
主な方法:
- マルチレファレンスCASPT2/pVTZレベルの理論が採用されました.
- 電子状態の幾何学とエネルギーが計算されました.
- CASPT2の分析は,代用されたフェニロキセニウムイオンについて行われました.
主要な成果:
- 閉じた殻のシングレット ((1)A(1)) は,フェニロキセニウムイオンの基本状態である.
- グラウンドシングレット状態と最下位のトリプルレット状態の間には,重要なエネルギーギャップ (22.1 kcal/mol) が存在します.
- シングレット・トリプルエネルギーギャップに対する置換効果を分析し,線形と非線形の相関を示した.
- メタドナー置換剤は,低エネルギーオープンシェル状態を安定させることができます.
結論:
- フェニロキセニウムイオンの電子状態の順序はフェニルニトロネと異なる.
- 計算の結果は,UV光電子スペクトロスコピーの割り当てを改訂することを示唆しています.
- フェニロキセニウムイオンの基底状態反応は,アリルニートレネよりもアリルニートレニウムイオンに似ているかもしれない.
関連する概念動画
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