对O3P) +D2反应的动态效应及其对 Λ-双体群体的影响
A Veselinova1, M Menéndez2, L González-Sánchez1
1Departamento de Química-Física, Universidad de Salamanca, Salamanca, 37008, Spain. pjambrina@usal.es.
Physical chemistry chemical physics : PCCP
|February 7, 2024
概括
量子散射计算揭示了O(3P) + D2反应的3A'潜在能量表面的意想不到的反应性. 这个表面,尽管理论预测,显示更高的横截面接近反应值,影响产品状态分布.
科学领域:
- 化学物理 化学物理
- 量子散射理论 量子散射理论
- 反应动力学 反应动力学
背景情况:
- 氧3P+D2反应发生在两个潜在能量表面 (PES):3A'和3A''.
- 这些 PES 对于直线配置具有退化性,但对于非直线方法则有分歧.
- 理论上的考虑表明,3A' PES应该不那么有反应性,因为能量在曲时会升.
研究的目的:
- 为了研究O ((3P) + D2反应在不同的PES上的反应性和产物状态分布.
- 为了使3A' PES上的较低反应能力的理论预期与计算发现相协调.
- 分析 PES 对称性和碰撞能量对散射动力学和 Λ-倍数群体的影响.
主要方法:
- 用量子散射计算来研究反应动态.
- 分析重点是反应截面和差异截面.
- 调查产品状态分布,特别是OD{2P) Λ-双元状态的人口.
主要成果:
- 与预期相反,3A' PES在不旋转反应剂的经典值附近表现出更高的反应截面.
- 在低总角动量时,两种 PES 之间的反应性差异更为明显.
- OD 的 π (A') Λ 双态在低和高碰撞能量中优先占据,有明显的散射机制.
结论:
- 3A' PES在O (3P) +D2反应中起着重要作用,特别是在低碰撞能量下,挑战了最初的理论假设.
- 较低的碰撞能量显示,通过向后分散在3A' PES上,对 Π(A') Λ-双倍人口的偏好.
- 高碰撞能量在3A'' PES上涉及不同的机制,也导致了P(A') Λ-倍的人口,但具有横向散射.
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