Intra- and Intermolecular Dynamics of pi-conjugated molecules and their dimers

π共轭分子及其二聚体的分子内和分子间动力学

• 批准号: 193502963
• 负责人: Professor Dr. Ingo Fischer
• 金额: --
• 依托单位: Institut für Physikalische und Theoretische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/193502963?language=en
• 关键词: Intra; Intermolecular; Dynamics; pi; conjugated

In the center of this project are polycyclic aromatic hydrocarbons and heterocycles that are of relevance in material science. We will study the processes that occur in these molecules after photoexcitation. The majority of experiments will be carried out in the gas phase, but complementary studies will be conducted in solution. Beside the isolated molecules we will also study their dimers to better understand energy transfer processes in larger aggregates. Gas-phase data allow a comparison with the results of highly accurate computations and thus provide a valuable benchmark for the theory on larger aggregates. The most relevant experimental method in this project will be picosecond time-resolved spectroscopy. In addition we want to establish time-resolved photoelectron spectroscopy using imaging detection of electrons in this phase of the project. An important class of molecules that moved into the focus of our research program are organic heterocycles like 1,8-naphthalic anhydride (NDCA) and 1,8-naphthalimide (NI). These molecules exhibit a competition between internal conversion and intersystem crossing on a ps-timescale. A detailed description of the competition in these model systems will contribute to a better understanding of the photoinduced dynamics in heterocycles in general.Furthermore we will continue the work on pyrene and study the formation of excimers as a function of excitation energy and of the chemical character of the substituent. Another system of interest is the tetracene dimer, which constitutes a model system for singlet fission. In this process an excited singlet state deactivates to two triplet states, which is proposed to be an efficient route for energy transfer in optoelectronic materials. Finally we will explore the structure and dynamics of strained rings, which are models for defects in carbon structures.We note that the close cooperation with theoretical and preparative groups at our department is of particular importance for this proposal.

该项目的核心是与材料科学相关的多环芳烃和杂环化合物。我们将研究光激发后这些分子中发生的过程。大多数实验将在气相中进行，但补充研究将在溶液中进行。除了孤立的分子之外，我们还将研究它们的二聚体，以更好地了解更大聚集体中的能量转移过程。气相数据可以与高精度计算的结果进行比较，从而为较大聚集体的理论提供有价值的基准。该项目中最相关的实验方法是皮秒时间分辨光谱。此外，我们希望在项目的这一阶段利用电子成像检测来建立时间分辨光电子能谱。成为我们研究项目重点的一类重要分子是有机杂环，如 1,8-萘二甲酸酐 (NDCA) 和 1,8-萘二甲酰亚胺 (NI)。这些分子在皮秒时间尺度上表现出内部转换和系间交叉之间的竞争。对这些模型系统中竞争的详细描述将有助于更好地理解杂环中的光致动力学。此外，我们将继续对芘的研究，并研究准分子的形成作为激发能和取代基化学特征的函数。另一个令人感兴趣的系统是并四苯二聚体，它构成了单线态裂变的模型系统。在此过程中，激发单重态失活为两个三重态，这被认为是光电材料中能量转移的有效途径。最后，我们将探索应变环的结构和动力学，这是碳结构缺陷的模型。我们注意到，与我们部门的理论和准备小组的密切合作对于这个提案特别重要。

项目成果

The excited-state structure and photophysics of isolated acenaphthylene

• DOI: 10.1016/j.chemphys.2018.05.017
• 发表时间: 2018-11-14
• 期刊: CHEMICAL PHYSICS
• 影响因子: 2.3
• 作者: Flock, Marco;Herbert, Max-Philipp;Fischer, Ingo
• 通讯作者: Fischer, Ingo

Isolated 2-hydroxypyrene and its dimer: a frequency- and time-resolved spectroscopic study

• DOI: 10.1039/d0nj02391d
• 发表时间: 2020-06
• 期刊: New Journal of Chemistry
• 影响因子: 3.3
• 作者: Hans-Christian Schmitt;I. Fischer;L. Ji;Julia Merz;T. Marder;Joscha Hoche;M. Röhr;R. Mitrić