在碎片化时对双离子OCS键的重新排列 - 实验和理论
Mahmoud Jarraya1,2,3, Måns Wallner4, Saida Ben Yaghlane2
1Université Gustave Eiffel, COSYS/IMSE, 5 Bd Descartes, 77454, Champs Sur Marne, France. majdi.hochlaf@univ-eiffel.fr.
Physical chemistry chemical physics : PCCP
|July 12, 2023
概括
OCS的光离子化会产生双电荷的离子,这些离子主要分离成CO+和S+离子对. 在这种解离过程中,COS2+的异构化起着关键作用.
科学领域:
- 化学物理 化学物理
- 原子和分子物理 原子和分子物理
- 量子化学 是一个量子化学.
背景情况:
- 双电荷的分子离子对于理解分子碎片化动态至关重要.
- 小分子的光离子化提供了一种途径来创造这些高能量的物种.
- 研究OCS2+的解离路径对于绘制潜在能量表面和反应机制至关重要.
研究的目的:
- 阐明通过光离子化形成的OCS2+离子的解离机制.
- 识别和描述OCS2+解离过程中涉及的异构体结构和潜在能量表面.
- 探索异构化在多电荷离子碎片化中的作用.
主要方法:
- 使用三倍和四倍的电子离子巧合光谱学.
- 在同位素结构和潜在能量表面上执行高级量子化学计算.
- 分析碎片离子对的动能释放和发起能量.
主要成果:
- 对于OCS2+来说,主要的解离通道是CO+ + S+离子对的形成.
- 两个预分离通道,包括一个新发现的COS2+元稳定状态,解释了不同电离能量的离子对形成.
- 以COS2+的异构化导致具有5.2 eV的动能释放的主导CO+ + S+通道,而直接碎片化则产生较低的动能释放.
结论:
- 对COS2+的异构化是OCS2+解离的一个重要途径.
- 该COS2+异构体还占小C++SO+离子对通道.
- 在解离之前的异构化可能是分离和多重电荷离子碎片化的常见机制.
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