测量和计算CO (7-0) 上调线强度
Aleksandr A Balashov1, Katarzyna Bielska1, Gang Li2
1Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziadzka 5, 87-100 Toruń, Poland.
The Journal of chemical physics
|June 21, 2023
概括
这项研究报告了首次使用空腔环向下光谱在一氧化碳 (CO) 中观察到高音 (7-0) 振动过渡. 实验和理论结果显示,这些弱光谱线具有很好的一致性.
科学领域:
- 分子光谱学 分子光谱学
- 量子化学 是一个量子化学.
- 频谱学是一种光谱学.
背景情况:
- 高频谱探测了基本转换之外的分子振动.
- 一氧化碳 (CO) 是各种化学和天体物理环境中至关重要的分子.
- 研究弱,高能过渡挑战实验和理论方法.
研究的目的:
- 通过实验测量和理论建模一氧化碳 (12C16O) 的第六高音 (7-0) 波段.
- 调查用于弱分子过渡的高色光谱学的可行性.
- 对高能振动状态的实验数据进行理论模型的验证.
主要方法:
- 使用频率稳定腔环降光谱 (CRDS) 来测量光谱线强度.
- 开发了一个理论模型,其中包含了ab initio双极时刻和半经验潜在能量曲线.
- 使用了多参考配置与戴维森校正的相互作用计算.
主要成果:
- 在可见范围 (14,30014,500厘米−1) 中,成功地观察并测量了CO在7-0高调频段的14条线的强度.
- 实验线的强度非常弱,低于2 × 10−29厘米分子−1在296 K.
- 在解决计算稳定性问题后,在几百分点的不确定性范围内实现实验和理论结果之间的一致.
结论:
- 这项研究表明,CRDS能够检测到像CO这样的分子中的弱,高音调过渡.
- 经过验证的理论模型为CO的高能振动状态提供了准确的预测.
- 精确的理论计算和对弱频段的实验测量对于推进分子光谱学和理解分子性质至关重要.
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