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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
电子亲和度,井深度和 cis-和 trans-HOCOCO 的振动光谱学
Christopher J Johnson1, Michael E Harding, Berwyck L J Poad
1Department of Physics, University of California-San Diego, La Jolla, California 92093-0340, USA.
Journal of the American Chemical Society
|November 8, 2011
概括
我们测量了HOCO(-) 和DOCO(-) 离子的振动光谱,确定了cis-和trans-HOCO的精确电子亲和力. 这些发现有助于识别化学反应中的HOCO基.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 量子化学 是一个量子化学.
背景情况:
- 碳基 (HOCO) 是燃烧和大气化学中的一个重要的中间体.
- 以前对HOCO异构体及其性质的实验数据有限,阻碍了准确的热化学计算.
研究的目的:
- 准确确定cis-和trans-HOCO同体的电子亲和力 (EA).
- 在气相中测量HOCO(-) 离子的低能振动模式.
- 为HOCO提供精确的热化学数据.
主要方法:
- 内部冷的HOCO(-) 和DOCO(-) 离子的振动分辨率光电子光谱.
- 高层次的初始计算.
主要成果:
- 对cis-HOCO同位素的三个低能振动模式的第一次气相测量.
- 重新分配的电子亲和度: cis-HOCO 在 1.51 ± 0.01 eV 和 trans-HOCO 在 1.37 ± 0.01 eV.
- 与OH + CO相比,对跨HOCO (1.07 ± 0.02 eV) 和 cis-HOCO (0.99 ± 0.02 eV) 的井深的确定.
- 实验结果和理论计算之间有很好的一致性.
结论:
- 该研究为HOCO异构体提供了精确的电子亲和度和振动频率.
- 获得的数据对于涉及HOCO的精确热化学计算至关重要.
- 这项研究有助于在复杂的化学环境中识别和理解HOCO基.
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