Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, CH-8093, Zurich, Switzerland.
Fukui Institute for Fundamental Chemistry, Kyoto University, Sakyo-ku, Kyoto, 606-8103, Japan.
Nat Commun. 2018 Aug 8;9(1):3162. doi: 10.1038/s41467-018-05292-4.
Time-resolved photoelectron spectroscopy (TRPES) is a useful approach to elucidate the coupled electronic-nuclear quantum dynamics underlying chemical processes, but has remained limited by the use of low photon energies. Here, we demonstrate the general advantages of XUV-TRPES through an application to NO, one of the simplest species displaying the complexity of a non-adiabatic photochemical process. The high photon energy enables ionization from the entire geometrical configuration space, giving access to the true dynamics of the system. Specifically, the technique reveals dynamics through a conical intersection, large-amplitude motion and photodissociation in the electronic ground state. XUV-TRPES simultaneously projects the excited-state wave packet onto many final states, offering a multi-dimensional view of the coupled electronic and nuclear dynamics. Our interpretations are supported by ab initio wavepacket calculations on new global potential-energy surfaces. The presented results contribute to establish XUV-TRPES as a powerful technique providing a complete picture of ultrafast chemical dynamics from photoexcitation to the final products.
时间分辨光电子能谱（TRPES）是阐明化学过程中电子-核量子动力学的有用方法，但由于光子能量较低，其应用受到限制。在这里，我们通过对最简单的物种之一 NO 的应用证明了 XUV-TRPES 的一般优势，该物种展示了非绝热光化学反应过程的复杂性。高光子能量能够从整个几何构型空间进行离化，从而获得系统的真实动力学。具体而言，该技术通过锥形交叉、电子基态中的大振幅运动和光解揭示动力学。XUV-TRPES 同时将激发态波包投影到许多末态上，提供了电子和核动力学的多维视图。我们的解释得到了新的全局势能面上从头计算波包计算的支持。所呈现的结果有助于确立 XUV-TRPES 作为一种强大的技术，从光激发到最终产物提供超快化学动力学的完整图景。
