在 D 中的同位素效应 D
Sarvesh Kumar1, Masamitsu Hoshino2, Boutheïna Kerkeni3,4
1Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
The journal of physical chemistry letters
|June 5, 2023
概括
研究H2O/D2O与碰撞中的电子转移,揭示了能量依赖的分支比和同位素效应. 这项研究首次确定了D2O的D-O键解离能.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 原子和分子碰撞 原子和分子碰撞
背景情况:
- 了解分子中的电子转移过程对于化学动力学至关重要.
- 水 (H2O) 和它的同位素 (D2O) 是化学和物理学的基本分子.
- 研究离子-分子反应为分子电子结构提供了洞察力.
研究的目的:
- 为了研究H2O/D2O与中性碰撞中的电子转移过程.
- 为了确定分支比和同位素效应的能量依赖性.
- 描述所涉及的电子状态和键解离能.
主要方法:
- 来自H2O/D2O与碰撞的负离子 (OH-/OD-, O-, H-/D-) 的飞行时间质谱.
- 在205 eV的冲击能量下,离子能量损失光谱.
- 在K-H2O/D2O系统中对未被占用的分子轨道进行量子化学计算.
主要成果:
- 观察到OH-/OD-,O-,和H-/D-负离子,具有能量依赖的分支比.
- 在D2O碰撞中观察到显著的同位素效应.
- 确定D2O的D-O键解离能量为5.41 ± 0.10 eV.
- 通过量子化学计算支持实验发现,识别涉及的电子状态.
结论:
- H2O/D2O与的电子转移碰撞显示出显著的能量依赖和同位素效应.
- 该研究提供了第一个在D2O中D-O键解离能量的实验性确定.
- 碰撞动态阐明了K-H2O/D2O系统中单双激发分子轨道的性质.
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