八面体鉄への光化学的経路 (((V). 超高速中赤外線スペクトロスコピーの原始プロセスと量子成果
Hendrik Vennekate1, Dirk Schwarzer, Joel Torres-Alacan
1Max-Planck-Institut für biophysikalische Chemie , Am Fassberg 11, 37077 Göttingen, Germany.
Journal of the American Chemical Society
|June 21, 2014
まとめ
光化学の研究では,可視光ではなく紫外線が溶液中の[[[シクラム-ac]Fe[III][N3][+]から高価鉄窒化物を生成することを明らかにしています. 光酸化は,光還元と結合分裂とフェムト秒で競合する.
科学分野:
- フォトケミストリー フォトケミストリー
- 無機化学 無機化学とは
- スペクトル顕微鏡検査です.
背景:
- 複合カチオン [ ((cyclam-ac) Fe (((III) (((N3))) (((+)) は,既知の光化学前駆体である.
- 以前の研究では,冷凍条件下で固体マトリックスを使用した.
研究 の 目的:
- 室温で液体溶液中の複合カチオンの光化学的原始現象を調査する.
- 溶液の振る舞いを,以前の冷凍マトリックス実験と比較する.
主な方法:
- 5秒間の時間解像度を持つ中赤外線 (fs-MIR) スペクトルスコピー.
- ステップスキャンのフーリエ変換赤外線スペクトロスコーピー.
- 波長が変動する刺激.
主要な成果:
- 可視光刺激 (LMCT帯) は,光酸化ではなく,リドックス中性アジド解離につながる.
- 紫外線の刺激により,高価鉄窒化物産物が形成されます.
- 光酸化は,光還元性のFe-N結合割れとN-N結合破裂とフェムト秒で競合する.
- 双子の再結合はピコ秒の時間スケールで起こります.
結論:
- 溶液の光化学は,冷凍マトリックス結果と大きく異なる.
- 紫外線光分解は高価鉄酸化窒素を生成するのに有効ですが,競合する経路を慎重に検討する必要があります.
- フォトオキシデーションのプライマリ量子産出量は,光子のエネルギーとともに増加する.
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