サイクロオクタテトレンベースの分子バランスによる循環水ダイマー移行状態の実験的水素結合エネルギーの評価
Henrik Ferdinand König1, Heike Hausmann1, Peter R Schreiner1
1Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
Journal of the American Chemical Society
|August 23, 2022
まとめ
サイクロオクタテトラエネ - ディメタノールイソマーを分子バランスとして使って,循環水ジメルの水素結合エネルギー (HBE) を決定した. この研究は,循環水ジメルの移行状態のHBEに関する新しい洞察を提供します.
科学分野:
- 物理化学
- コンピュータ化学
- 超分子化学
背景:
- 水素結合エネルギー (HBE) は,循環水ダイマーの移行状態を直接決定することは困難である.
- サイクロオクタテトレーン-1,4-ジメタノール (1,4) とサイクロオクタテトレーン-1,6-ジメタノール (1,6) のイソメアは分子モデルとして用いられる.
- 1,6-同位体は,水ダイマー移行状態を模倣する周期的平面幾何学を持つ分子内水素結合を特徴とする.
研究 の 目的:
- 循環水ジメルの移行状態のアクセシブルな水素結合エネルギー (HBE) を決定する.
- 1,6-同位体内の水素結合を特徴付け,循環水二重体と比較する.
- 分子バランスのためのギブスの自由エネルギーを実験的に測定する.
主な方法:
- 核磁気共振 (NMR) スペクトロスコピーを用いた実験的な測定.
- SAPT2+(3) δMP2,M06-2XD3(0),およびDLPNO-CCSD(T) の計算を含む計算研究.
- 分子の量子理論 (QTAIM) の記述子が使用された.
主要な成果:
- 1,6-同位体における水素結合は,Cs対称サイクリック水ダイマー移行状態の相互作用に非常に似ています.
- 折りたたみのギブス自由エネルギー (ΔGeq) は,様々な有機溶媒で測定された.
- 実験データと計算データを組み合わせて,周期的な水ダイマーのHBEを推定する.
結論:
- この研究では,周期的な水ダイマーとその移行状態のHBEを成功裏に推定しています.
- 分子バランスアプローチは,他の方法ではアクセスできないHBEsを研究するための有効な方法を提供します.
- この発見は 水のクラスターにおける水素結合の理解を深めるのに寄与しています
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