对二氧化乙的化学发光分解的理论研究
Fengyi Liu1, Yajun Liu, Luca De Vico
1Department of Theoretical Chemistry, Lund University, Chemical Center, P.O. Box 124, SE-221 00 Lund, Sweden.
Journal of the American Chemical Society
|April 11, 2009
概括
不被替代的二氧化乙分解涉及两个过渡状态和形交叉点. 过渡状态附近的状态相互作用解释了化学发光 (n,sigma*) 状态人口.
科学领域:
- 理论化学 理论化学
- 化学物理 化学物理
背景情况:
- 单分子分解反应是化学的基础.
- 化学发光,即化学反应期间的光辐射,是关键的现象.
- 迪奥克塞坦分解是研究化学发光的一个模型系统.
研究的目的:
- 为了研究未被替代的二氧化乙的单分子化学发光分解.
- 阐明反应机制,包括过渡状态和中间体.
- 为了确定化学发光状态人口的起源.
主要方法:
- 利用完整的活性空间自相一致场理论 (CASSCF).
- 使用多态二次多配置扰动理论 (MS-SCT) 来进行能量校正.
- 分析了反应路径,过渡状态,形交叉点和电子状态.
主要成果:
- 确定了两个过渡状态 (O-O和C-C裂隙) 和两个形交叉点.
- 发现了一种稳定的基中间体.
- 观察到 (1) ((n,sigma*), (3) ((n,sigma*) 和 (1) ((sigma,sigma*) 状态在第二个过渡状态附近的能量接近.
- 在过渡状态附近找到形交叉点,首先有路径分叉.
结论:
- 这项研究揭示了二氧化乙分解过程中复杂的电子状态相互作用.
- 形交叉点和状态合对反应路径至关重要.
- 振动分布和状态间相互作用解释了化学发光 (n,sigma*) 状态的种群.
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