Garcia Gustavo A, Dontot Léo, Rapacioli Mathias, Spiegelman Fernand, Bréchignac Philippe, Nahon Laurent, Joblin Christine
Synchrotron SOLEIL, L'Orme des Merisiers, Départamentale 128, 91190 Saint Aubin, France.
Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse III - Paul Sabatier, CNRS, CNES, 9 avenue du Colonel Roche, BP 44346, F-31028 Toulouse, France.
Phys Chem Chem Phys. 2023 Feb 8;25(6):4501-4510. doi: 10.1039/d2cp05679h.
We present a combined experimental and theoretical study on the dissociative ionisation of clusters of pyrene. We measured the experimental appearance energies in the photon energy range 7.2-12.0 eV of the fragments formed from neutral monomer loss for clusters up to the hexamer. The results obtained show a deviation from statistical dissociation. From electronic structure calculations, we suggest that the role of excited states must be considered in the interpretation of experimental results, even in these relatively large systems. Non-statistical effects in the dissociative ionization process of polycyclic aromatic hydrocarbon (PAH) clusters may have an impact on the assessment of mechanisms determining the stability of these clusters in astrophysical environments.
我们展示了一项关于芘团簇离解电离的实验与理论相结合的研究。我们测量了在7.2 - 12.0 eV光子能量范围内，直至六聚体的团簇因中性单体损失而形成的碎片的实验出现能。所得结果显示出与统计解离的偏差。通过电子结构计算，我们认为即使在这些相对较大的体系中，在解释实验结果时也必须考虑激发态的作用。多环芳烃（PAH）团簇离解电离过程中的非统计效应可能会影响对决定这些团簇在天体物理环境中稳定性的机制的评估。
