Photoelectron Spectroscopy of Oppositely Charged Molecular Switches in the Aqueous Phase: Theory and Experiment
Photoelectron Spectroscopy of Oppositely Charged Molecular Switches in the Aqueous Phase: Theory and Experiment
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DOI：
10.1021/acs.jpclett.3c00828
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发表时间：
2023-06-26
影响因子：
5.7
通讯作者：
Gozem, S.
中科院分区：
文献类型：
--
作者：
Ikonnikov, E.;Paolino, M.;Gozem, S.
XUV光电子能谱（XPS）是表征分子电子结构的有力手段。然而，正确的解释结果在凝聚相需要的理论模型，占溶剂化。本文介绍了两种有机仿生分子开关NAIP和p-HDIOP的实验性水相XPS。这些开关在结构上相似，但具有相反的电荷，因此提出了一个严格的solvationmodels的基准，需要重现观察到的&UDelta;eBE = 1.1 eV的差异相比，在气相中预测的8 eV的差异电子结合能。我们目前的计算使用隐式和explicitsolvent模型。后者采用平均溶剂静电构型和自由能梯度（ASEC-FEG）方法。非平衡极化连续模型和ASEC-FEG计算都给出了与实验符合良好的垂直结合能。反离子，明确占在ASEC-FEG，有助于稳定的分子状态和减少溶剂化后的& U δ;eBE。
XUV photoelectron spectroscopy (XPS) is a powerful methodfor investigatingthe electronic structures of molecules. However, the correct interpretationof results in the condensed phase requires theoretical models thataccount for solvation. Here we present experimental aqueous-phaseXPS of two organic biomimetic molecular switches, NAIP and p-HDIOP. These switches are structurally similar, but haveopposite charges and thus present a stringent benchmark for solvationmodels which need to reproduce the observed & UDelta;eBE = 1.1 eV differencein electron binding energy compared to the 8 eV difference predictedin the gas phase. We present calculations using implicit and explicitsolvent models. The latter employs the average solvent electrostaticconfiguration and free energy gradient (ASEC-FEG) approach. Both nonequilibriumpolarizable continuum models and ASEC-FEG calculations give verticalbinding energies in good agreement with the experiment for three differentcomputational protocols. Counterions, explicitly accounted for inASEC-FEG, contribute to the stabilization of molecular states andreduction of & UDelta;eBE upon solvation.