从高分辨率的富里埃变换和QCL红外测量中对2-二的Trans和Cis对应物的Rovibrational光谱学测量
Sathapana Chawananon1, Pierre Asselin1, Jordan A Claus2
1Sorbonne Université, MONARIS, CNRS, UMR8233, 4 Pl Jussieu, F-75005 Paris, France.
Molecules (Basel, Switzerland)
|May 27, 2023
概括
本研究使用高分辨率光谱学对2-二 (2-FF),一种大气污染物进行了表征. 了解它的振动带和热带对于准确的大气建模和辐射强迫评估至关重要.
科学领域:
- 大气化学 大气化学
- 分子光谱学 分子光谱学
- 环境科学 环境科学
背景情况:
- 2- (2-FF) 是生物质燃烧产生的主要大气污染物.
- 2-FF有助于二次有机气溶的形成,其辐射强迫作用尚不清楚.
- 需要对2-FF进行精确的监测和反应性特征.
研究的目的:
- 进行对2-FF对应体 (跨和 cis) 进行广泛的喷气冷却反振动研究.
- 在中红外区域中导出振动带的分子参数.
- 为了重建室温光谱,并确定振动横截面,用于大气模型.
主要方法:
- 利用两个互补的高分辨率里埃变换和量子级联激光谱仪与超音速喷射器相结合.
- 记录低温 (20-50 K) 的喷气冷却光谱,用于精确的参数确定.
- 额外推算低温数据以重建室温光谱并计算带横截面.
主要成果:
- 从成千上万的光谱线的全球匹配中,获得了对trans-和cis-2-FF的可靠激发状态分子参数.
- 成功重建了HITRAN数据库的2-FF频谱在298.15K的高精度.
- 证明热带对室温频谱的贡献很大 (40-63%),因此需要将它们纳入模拟.
结论:
- 该研究为2-FF提供了关键的光谱数据,这对大气研究至关重要.
- 准确建模2-FF对大气的影响需要包括热带贡献.
- 这项工作改善了对2-FF在大气过程和辐射强迫中的作用的理解.
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