N + OH反応を通して低温での原子根の反応性を明らかにする

Julien Daranlot¹, Mohamed Jorfi, Changjian Xie

¹Université de Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, F-33400 Talence, France.

Science (New York, N.Y.)

|December 17, 2011

まとめ

この研究では,超音速フロー原子炉を使用して,急速なN + OH反応運動を調査しました. 結果は,星間雲のガス相窒素形成についての洞察を提供します.

科学分野:

化学動力学化学動力学
アストロケミストリーアストロケミストリー
物理化学物理化学

背景:

フリーラジカルを含む反応は,様々な化学プロセスにおいて極めて重要です.
2つの不安定なラジカル間の反応は,実験上の課題のために,あまり理解されていない.
N + OH反応は,大気および恒星間化学における重要なプロセスです.

研究の目的:

障壁のないN((4) S) + OH((2) Π) → H((2) S) + NO(2) Π) の反応の速度を実験的に決定する.
実験結果と理論的量子力学計算を比較する.
星間雲における分子窒素のガス相形成機構を解明する.

主な方法:

運動実験は超音速フロー (ラバルノズル) 原子炉で行われた.
原子窒素は,マイクロ波放電法を使用して生成されました.
反応動態は,相対速度法を用いて監視された.

主要な成果:

測定されたN + OHの反応速度は,理論的な予測とよく一致していることが判明しました.
正確かつ近似の量子力学的計算の両方が実験データを裏付けました.
この研究は,N + OH反応に関する貴重な運動データを提供します.

結論:

N + OH反応は理論的モデルと一致して急速に進行します.
実験データにより,ラジカル-ラジカル反応の量子力学計算の妥当性が証明されている.
この発見は,星間環境における窒素含有分子形成の理解に貢献する.

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