パーメチル化シロキサンとエーテルにおける超結合的相互作用:SiO結合の性質
1Department of Chemistry, University of Wisconsin, Madison Wisconsin 53706, USA.
Journal of the American Chemical Society
|March 29, 2013
まとめ
シリコンは,シリコン-酸素結合における電子の移転が強化されたため,驚くほど低い酸素基本性を表しています. この超結合は,それらの安定性を説明し,伝統的な結合と反応性モデルに挑戦します.
科学分野:
- 材料科学 材料科学とは
- コンピューティング・ケミストリー
- ポリマー化学のポリマー化学について
背景:
- シリコン-酸素 (Si-O) 結合は,シリコンポリマーの骨幹を形成する.
- Si-O-Si結合の酸素原子は,通常,そのアニオン性に基づく期待に反して,低塩基性を示します.
研究 の 目的:
- シリコンポリマーにおける酸素の低塩基性の背後にある根本的な理由を調査する.
- シリコンポリマーを完全メチル化デリバティブを使用してより正確にモデル化するために.
主な方法:
- ハイブリッド密度関数理論 (DFT) の計算.
- ナチュラル・ボンド・オービタル (NBO) 分析.
- 理想化されたディジロキサンとジメチルエーテルモデルとの比較.
主要な成果:
- Si-O結合とC-O結合のハイパーコンジュガティブデロカライゼーションの強化は,パーメチル化されたシリコンで確認され,強調されました.
- NBOの分析は,Si-O-Si結合の安定性と低塩基性に寄与する特定の軌道重複を明らかにしました.
- アナログにおけるステリック歪みは,観測された電子効果を否定しなかった.
結論:
- シリコン酸素の低塩基性は,ハイパー結合による有意な電子離位に起因する.
- これらの発見は,Si-O結合と酸塩相互作用のイオンおよび従来の静電モデルに挑戦しています.
- この研究は,シリコンポリマーの安定性と反応性をより深く理解するためのものです.
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