分子内複合体の"違法"二極結合アニオン
Valery F Sidorkin1, Elena F Belogolova1, Evgeniya P Doronina1
1A. E. Favorsky Irkutsk Institute of Chemistry , Siberian Branch of the Russian Academy of Sciences Favorsky, 1 , Irkutsk 664033 , Russian Federation.
Journal of the American Chemical Society
|January 4, 2020
まとめ
この研究では,二極結合 (DB) 電子がシラトランケージ分子で異常なSi-N結合の縮小を引き起こすことが明らかになった. この構造の変化は 電子離散エネルギーだけでなく 二極電流と分子幾何学に依存しています
科学分野:
- コンピュータ化学
- 量子化学について
- 分子構造とダイナミクス
背景:
- シラトランは様々な化学分野での応用の可能性のあるケージ化合物である.
- 二極結合 (DB) アニオンとは,過剰な電子が分子二極モメントによって弱く結合される種である.
- 電子と分子構造の相互作用を理解することは 化学的振る舞いを予測するのに不可欠です
研究 の 目的:
- シラタン分子 (XSi(OCH2CH2) 3N) の構造に対する二極結合電子の影響を調査する.
- シラトランから派生したDBアニオンの形成と構造的再配置を制御する要因を探求する.
- シラトランDBアニオンの実験データと計算結果を比較する.
主な方法:
- 高精度カップリングクラスター計算,特にCCSDとCCSD (T) 方法.
- レテルマール電子光電子スペクトロスコーピー (RET-PES) を用いた実験測定.
- 分子幾何学,二極運動,電子分離エネルギーの分析.
主要な成果:
- シラトランからDBアニオンが形成されると,核間のSi··N距離の異常な縮小が観察された.
- X=Clの0.15 Åの記録的縮小が観測され,以前知られているDBアニオンを超えた.
- DBアニオン形成は,二極モメントの大きさとN ((CH2) 3) のピラミダ性によって影響を受けます.
結論:
- シラトランの過剰な電子結合に対する構造的反応はユニークで複雑である.
- 構造的再配置の程度は,Si-N結合の縮小による二極 Moment 増加率によって決まります.
- これらの発見は,置換された5-アザビサイクロ[3.3.3]アンデカンの幅広い範囲に適用できます.
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