大气中的集群I:氧化酸和氧化物的计算基准和滴度形成
Morten Engsvang1, Haide Wu1, Jonas Elm1
1Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark.
ACS omega
|July 29, 2024
概括
这项研究对大气新粒子形成中的化合物的计算方法进行了基准测试. 它发现相对论效应对于准确计算集群稳定性至关重要,之前的研究可能高估了它们的影响.
科学领域:
- 大气化学 大气化学
- 量子化学 是一个量子化学.
- 环境科学 环境科学
背景情况:
- 化合物与大气新粒子形成有关,但它们的确切作用尚不清楚.
- 之前对集群的量子化学研究缺乏全面的准确性基准.
研究的目的:
- 为了对研究大气集群形成中的物种的计算方法进行比较.
- 准确量化含有的集群的稳定性,这与新颗粒的形成有关.
主要方法:
- 评估了各种单体和二元几何学的计算方法,热校正和旋转轨道合效应.
- 确定了电子能量校正理论的最准确水平,包括相对论效应.
- 应用了经过验证的方法来计算含二元体的结合自由能量.
主要成果:
- 使用 ωB97X-D3BJ/aug-cc-pVTZ-PP 或 M06-2X/aug-cc-pVTZ-PP 的优化结构提供了最佳的热贡献.
- 识别了ZORA-DLPNO-CCSD(T0) /SARC-ZORA-TZVPP () 和ma-ZORA-def2-TZVPP (非),用于精确的电子能量校正.
- 证实了先前的趋势,但由于忽视了相对论效应,在先前的研究中发现了集群稳定性 (几个kcal/mol) 的显著高估.
结论:
- 准确计算含有的集群稳定性需要考虑相对论效应.
- 这些星团对新粒子形成的先前理论贡献可能被高估了.
- 这项工作为未来关于在大气化学中的作用的研究提供了经过验证的方法.
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