硫黄一酸化物-ヒドロキシル基複合体の捕獲
Changyun Chen1, Bo Lu1, Xiaofang Zhao1
1College of Chemistry, Chemical Engineering and Materials Science , Soochow University , 215123 Suzhou , China.
Journal of the American Chemical Society
|January 16, 2020
まとめ
研究者達は,気象化学の重要な中間物質である,水素結合した硫黄一酸化水素基複合体 (•OH··OS) を特定した. この発見は 大気中の二酸化硫黄の反応の理解を 進めてくれます
科学分野:
- 大気化学
- 物理化学
- スペクトロスコーピー
背景:
- 大気中の二酸化硫黄 (SO2) の循環には,多くの中間物質が含まれるが,そのいくつかは十分に理解されていない.
- 水素結合の硫黄一酸化物-ヒドロキシル基複合体 (•OH··OS) は,SO2の大気化学の欠落リンクであると仮定されている.
研究 の 目的:
- 難解な水素結合硫黄一酸化物-水酸化基複合体 (•OH··OS) を実験的に生成し,特徴づけること.
- OH··OS複合体の熱安定性と変換運動を調査する.
主な方法:
- 低温アルゴン (Ar) マトリックスにおけるスルフィニル基 (HOSO) の266 nmレーザー光分解によるOH·OS複合体の生成.
- 赤外線 (IR) のスペクトロスコピカル特徴付け,デュテレーション研究を含む.
- 活性化バリアと運動同位体効果を決定する温度依存の運動研究 (15.0 〜 21.0 K)
主要な成果:
- 水素結合のOH·OS複合体の生成とスペクトル検出に成功した.
- 低活性化バリア 0.33 ± 0.11 kcal mol-1で,OH··OSを再びHOSOに熱変換することが観察された.
- 16.0 Kで2. 4の有意なH/D運動同位体効果を測定し,提案された反応メカニズムを支持した.
結論:
- この研究は,水素結合のOH·OS複合体の存在に関する最初の実験的証拠を提供する.
- 発見は,SO2の大気化学における一時的な中間物質として,その環境運命を理解するために不可欠であることを確認した.
- 決定された運動パラメータは,硫黄化合物の大気モデリングのための貴重なデータを提供します.
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