Intra- and intermolecular dispersion forces: Understanding complex formation, aggregation, and the effect of solvation using a bottom-up approach

该研究计划的目标是通过使用高分辨率旋转光谱系统地探索模型系统，显着推进目前对分散相互作用在分子识别和分子内结构中的作用的理解。我们将继续我们成功的工作，光谱研究和表征分子系统在气相中，以了解和量化内和分子间的相互作用。在自下而上的方法中，我们将研究与理解分子聚集相关的基本过程，最终从气体到体相的过渡，以及溶剂化对分散的影响。对于第二个资助期，我们现在可以建立一个坚实的，富有成效的和创造性的合成，光谱和理论化学小组网络，如上所述。我们提出以下几个方面的工作：在项目1中，我们的目标是进一步定性和定量地研究分散的各种分子复合物的作用。我们将继续在醚-醇复合物方面的工作（在第一个资助期内已经有了一些惊喜），并与我们的合作伙伴团队合作，将其扩展到酮-醇复合物以及手性物质。我们的目标是全面了解色散贡献如何影响复合物的结构，以及构象柔性扮演的角色。在第二个项目中，我们将研究分子的聚集，例如具有扩展π系统的分子，从而在分子水平上探索从单个分子到整体的转变。对于与燃烧有关的烟尘颗粒的形成以及与天体化学有关的尘埃颗粒的形成，分子-分子累积机制的预期结果也将是令人感兴趣的。在项目3中，我们将研究溶剂化作用如何影响色散。我们将研究分子复合物，如二苯基醚-甲醇，并研究如何通过逐步溶剂化的复合物调节簇形成的结构偏好。分子射流中的受控条件非常适合这种实验。 我们的目标是了解溶剂化的效果如何取决于不同的分子系统，以及如何预测和最终控制。

The goal of the research program is to significantly advance the current understanding of the role of dispersion interaction in molecular recognition and intramolecular structures by systematically exploring model systems using high-resolution rotational spectroscopy. We will continue our successful work on spectroscopically investigating and characterizing molecular systems in the gas phase to understand and quantify intra- and intermolecular interactions. In a bottom-up approach, we will study basic processes relevant for understanding molecular aggregation and finally the transition from the gas to the bulk phase, as well as the influence of solvation on dispersion. For the second funding period, we can now build on a solid, fruitful, and creative network of synthesis, spectroscopy, and theoretical chemistry groups, as described above. We propose to work on the following aspects:In project 1, it is our goal to further investigate qualitatively and quantitatively the role of dispersion for a variety of molecular complexes. We will continue our work on ether-alcohol complexes (which already let to a number of surprises in the first funding period) and extend it to ketone-alcohol complexes as well as chiral species, in collaboration with our partner groups. We aim at gaining a complete understanding of how dispersion contributions influence the structures of complexes and which role conformational flexibility plays.In a second project, we will study aggregation of molecules, such as those with extended π systems, and we will thus explore the transition from individual molecules to the bulk on the molecular level. The anticipated results on a molecule-by-molecule build-up mechanism will also be of interest for the formation of soot particles as relevant for combustion as well as of dust grains as relevant for astrochemistry.In project 3, we will investigate how dispersion is influenced by solvation. We will study molecular complexes, such as diphenylether-methanol, and investigate how structural preferences upon clusters formation are modulated by stepwise solvation of the complex. The controlled conditions in a molecular jet are ideally suited for such experiments. We aim at understanding how the effect of solvation depends on the different molecule systems, and how this can be predicted and finally controlled.