Couto Rafael C, Kjellsson Ludvig, Ågren Hans, Carravetta Vincenzo, Sorensen Stacey L, Kubin Markus, Bülow Christine, Timm Martin, Zamudio-Bayer Vicente, von Issendorff Bernd, Lau J Tobias, Söderström Johan, Rubensson Jan-Erik, Lindblad Rebecka
Department of Theoretical Chemistry and Biology, School of Chemistry, Biotechnology and Health, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden and European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany.
Phys Chem Chem Phys. 2020 Jul 22;22(28):16215-16223. doi: 10.1039/d0cp02207a.
We present and analyze high resolution near edge X-ray absorption fine structure (NEXAFS) spectra of CO+ at the carbon and oxygen K-edges. The spectra show a wealth of features that appear very differently at the two K-edges. The analysis of these features can be divided into three parts; (i) repopulation transition to the open shell orbital - here the C(1s) or O(1s) to 5σ transition, where the normal core hole state is reached from a different initial state and different interaction than in X-ray photoelectron spectroscopy; (ii) spin coupled split valence bands corresponding to C(1s) or O(1s) to π* transitions; (iii) remainder weak and long progressions towards the double ionization potentials containing a manifold of peaks. These parts, none of which has correspondence in NEXAFS spectra of neutral molecules, are dictated by the localization of the singly occupied 5σ orbital, adding a dimension of chemistry to the ionic NEXAFS technique.
我们展示并分析了CO⁺在碳和氧K边的高分辨率近边X射线吸收精细结构（NEXAFS）光谱。这些光谱显示出大量特征，在两个K边呈现出非常不同的表现。对这些特征的分析可分为三个部分：（i）向开壳层轨道的再填充跃迁——这里指C(1s)或O(1s)到5σ跃迁，其中从不同的初始态并通过与X射线光电子能谱中不同的相互作用达到正常的芯态空穴；（ii）对应于C(1s)或O(1s)到π*跃迁的自旋耦合分裂价带；（iii）向包含多个峰的双电离势的其余微弱且长的进展。这些部分在中性分子的NEXAFS光谱中均无对应，它们由单占据5σ轨道的局域性决定，为离子NEXAFS技术增添了化学维度。
