波恩-奥本海默近似在F+o-D2 -> DF + D反应中的分解
Li Che1, Zefeng Ren, Xingan Wang
1State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, People's Republic of (P. R.) China.
Science (New York, N.Y.)
|August 25, 2007
概括
激发的原子 (F*) 在D2反应中表现出比基态 (F) 更高的反应性,即使在理论上是被禁止的. 量子计算证实了对非非相应的抽象反应的实验发现.
科学领域:
- 化学动力学 化学动力学
- 量子化学 是一个量子化学.
- 分子散射 分子散射
背景情况:
- 外热三原子抽象反应是化学的基础.
- 对于反应动态来说,了解电子非反性至关重要.
研究的目的:
- 研究与 (D2) 的地面 (F) 和激发 (F*) 旋转轨道状态的反应性.
- 确定碰撞能量对反应动力学和电子非相应性的影响.
主要方法:
- 使用交叉光束散射实验来测量积分和微分横截面.
- 采用多态,量子反应散射计算进行理论分析.
主要成果:
- 观察到F*在低碰撞能 (0.25-1.2 kcal/mol) 时比F反应性大约1.6倍.
- 发现波恩-奥本海默 (BO) 允许反应在碰撞能量增加时占主导地位.
- 在实验数据和量子散射计算之间取得了很好的一致性.
结论:
- 实验和理论结果证实了在抽象反应中对电子非相反性的理解.
- 该研究验证了用于预测复杂反应动态的量子散射计算.
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