Ponzi Aurora, Sapunar Marin, Došlić Nadja, Decleva Piero
Department of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia.
Istituto Officina dei Materiali IOM-CNR and Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy.
Molecules. 2022 Mar 10;27(6):1811. doi: 10.3390/molecules27061811.
Photoelectron angular distribution (PAD) in the laboratory frame for randomly oriented molecules is typically described by a single anisotropy parameter, the so-called asymmetry parameter. However, especially from a theoretical perspective, it is more natural to consider molecular photoionization by using a molecular frame. The molecular frame PADs (MFPADs) may be used to extract information about the electronic structure of the system studied. In the last decade, significant experimental efforts have been directed to MFPAD measurements. MFPADs are highly characterizing signatures of the final ionic states. In particular, they are very sensitive to the nature of the final state, which is embodied in the corresponding Dyson orbital. In our previous work on acetylacetone, a prototype system for studying intra-molecular hydrogen bond interactions, we followed the dynamics of the excited states involved in the photoexcitation-deexcitation process of this molecule. It remains to be explored the possibility of discriminating between different excited states through the MFPAD profiles. The calculation of MFPADs to differentiate excited states can pave the way to the possibility of a clear discrimination for all the cases where the recognition of excited states is otherwise intricate.
在实验室坐标系中，对于随机取向分子的光电子角分布（PAD）通常由单个各向异性参数（即所谓的不对称参数）来描述。然而，特别是从理论角度来看，使用分子坐标系来考虑分子光电离更为自然。分子坐标系中的PAD（MFPAD）可用于提取有关所研究系统电子结构的信息。在过去十年中，大量实验工作都致力于MFPAD测量。MFPAD是最终离子态的高度特征性标志。特别是，它们对最终状态的性质非常敏感，这体现在相应的戴森轨道中。在我们之前关于乙酰丙酮（一种用于研究分子内氢键相互作用的原型系统）的工作中，我们追踪了该分子光激发 - 去激发过程中涉及的激发态动力学。通过MFPAD轮廓区分不同激发态的可能性仍有待探索。计算MFPAD以区分激发态可以为所有难以识别激发态的情况开辟清晰区分的可能性之路。
