有機溶媒における水素化陽子のH ((aq) +の性質
Evgenii S Stoyanov1, Irina V Stoyanova, Fook S Tham
1Department of Chemistry, University of California, Riverside, California 92521, USA. evgenii.stoyanov@ucr.edu
Journal of the American Chemical Society
|August 15, 2008
まとめ
赤外線スペクトロスコピーは,H ((H2O) n ((+)) 溶液の核種はH7O3 ((+)) イオンであり,予想されるEigen型またはZundel型イオンではないことを明らかにします. この発見は,水のクラスタカチオン構造に関する以前の仮定に異議を唱える.
科学分野:
- 物理化学 物理化学
- スペクトロスコーピーは,スペクトロスコーピーを用います.
- 無機化学 無機化学とは
背景:
- 水のクラスターカチオンは,水系における陽子の移転を理解する上で不可欠です.
- 以前の研究では,Eigen型 (H3O(H2O) 3+) またはZundel型 (H5O2(H2O) 4+) のイオンの存在をしばしば想定していました.
研究 の 目的:
- 溶液中のH(H2O) n(+) カチオン (n=3-8) の構造的性質を調査する.
- カーボランカウンテリアンの存在において,支配的なプロトネート水種を明確にするために.
主な方法:
- 赤外線 (IR) スペクトロスコーピーは,カチオンを研究するために使用されました.
- ベンゼンとジクロロエタン溶液で実験を行った.
主要な成果:
- この研究では,Eigen型またはZundel型陽子化された水クラスターの証拠は見つかりませんでした.
- H7O3 ((+) イオンが主たるコア種として特定されました.
- カーボランカウンターイオンは,コア水カチオン構造を大幅に変化させなかった.
結論:
- H7O3 ((+)) イオンは,これらの特定の溶液条件下では,安定した,一般的な種です.
- この発見は,プロトン水群の構造モデルの再評価を必要とします.
- 弱塩基カルボランのカウンテリアは,固有の水カチオン行動の観察を可能にします.
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