Molecular-Frame Photoelectron Angular Distributions of CO in the Vicinity of Feshbach Resonances: An XCHEM Approach
Molecular-Frame Photoelectron Angular Distributions of CO in the Vicinity of Feshbach Resonances: An XCHEM Approach
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DOI：
10.1021/acs.jctc.1c00480
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发表时间：
2021-09-16
影响因子：
5.5
通讯作者：
Martin, Fernando
中科院分区：
文献类型：
--
作者：
Borras, Vicent J.;Gonzalez-Vazquez, Jesus;Martin, Fernando
超短XUV脉冲的出现推动了精确的理论计算的发展，以描述电子关联发挥重要作用的区域的分子电离。在这里，我们提出了一种XCHEM方法的扩展，以评估实验室和分子框架光电子角分布在预计会出现费什巴赫共振的区域。这种方法的性能在CO分子中得到了证明，但有关Feshbach共振的信息非常稀少。我们发现，共振的存在对光电子角分布有很大的影响，以至于它们可以完全逆转在直接非共振光电离中观察到的优先电子发射方向。这是当共振衰减时，分子的电子结构发生显著变化的结果，这种影响主要是由电离连续体中的电子相关性驱动的。因此，本方法有助于解释这种分子和更复杂分子中角度分辨的光致电离时间延迟。
The advent of ultrashort XUV pulses is pushing for the development of accurate theoretical calculations to describe ionization of molecules in regions where electron correlation plays a significant role. Here, we present an extension of the XCHEM methodology to evaluate laboratory- and molecular-frame photoelectron angular distributions in the region where Feshbach resonances are expected to appear. The performance of the method is demonstrated in the CO molecule, for which information on Feshbach resonances is very scarce. We show that photoelectron angular distributions are dramatically affected by the presence of resonances, to the point that they can completely reverse the preferred electron emission direction observed in direct nonresonant photoionization. This is the consequence of significant changes in the electronic structure of the molecule when resonances decay, an effect that is mostly driven by electron correlation in the ionization continuum. The present methodology can thus be helpful for the interpretation of angularly resolved photoionization time delays in this and more complex molecules.