ビス (トライフルオロメチルスルフォニル) アミドアニオンを含むアリファティックイオン液体における過剰電子電荷のダイナミクス
Changhui Xu1, Aleksander Durumeric, Hemant K Kashyap
1Department of Chemistry, University of Iowa , Iowa City, Iowa 52241, United States.
Journal of the American Chemical Society
|October 26, 2013
まとめ
イオン性液体の余分な電子は,アニオンに素早く局所化し,50フェムト秒以内に断片化を開始します. この電荷の局所化はスペクトルの移行を劇的に変化させ,帯域内から電子伝送ダイナミクスにシフトします.
科学分野:
- 物理化学 物理化学
- マテリアルサイエンス 材料科学
- 化学物理 化学物理
背景:
- 以前の研究では,室温のイオン性液体 (RTIL) の余剰電子の空間的分布を調査した.
- 予期せぬことに,過剰な負の電荷は,いくつかのアルキルアモニウム系において,カチオンではなくアニオンに宿っていることが判明しました.
研究 の 目的:
- RTILにおける過剰電子電荷の時間的進化を検証する.
- 電荷の局所化と,その後のアニオン行動のダイナミクスを理解するために.
主な方法:
- 時間解像度スペクトロスコピーは,時間解像度スペクトロスコピーを用います.
- イオン性液体における電子ダイナミクスの計算モデリング
- 超高速電子伝送の研究
主要な成果:
- アルキルアモニウムおよびピロリジニウムベースのイオン性液体に先行して位置移転した余剰の電子は,50フェムト秒以内にbis ([Tf2N (−)) アニオン ([Tf2N (−)) ]アニオンに局所化する.
- アニオンの局所化は,断片化のプロセスを引き起こす.
- スペクトルの移行は,アニオン断片として帯域内から電子伝送ダイナミクスに変化します.
結論:
- RTIL の余剰電子の動態は時間スケールに依存し,局所化と断片化は急速に発生します.
- ビス (Trifluoromethylsulfonyl) アミドアニオンは,余剰の電子電荷の分散に重要な役割を果たします.
- これらの超高速プロセスの理解は,イオン性液体と電子伝送を含むアプリケーションにとって非常に重要です.
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