Robust fitting of core level photoemission spectra is often central to reliable interpretation of X‐ray photoelectron spectroscopy (XPS) data. One key element is employment of the correct line shape function for each spectral component. In this study, we consider this topic, focusing on XPS data from atomic adsorbates, namely, O and S, on Fe(110). The potential of employing density functional theory (DFT) for generating adsorbate projected electronic density of states (PDOS) to support line shape selection is explored. O 1s core level XPS spectra, acquired from various ordered overlayers of chemisorbed O, all display an equivalent asymmetric line shape. Previous work suggests that this asymmetry is a result of finite O PDOS in the vicinity of the Fermi level, allowing O 1s photoexcitation to induce a weighted continuum of final states through electron‐hole pair excitation. This origin is corroborated by O DFT‐PDOS generated for an optimised five‐layer Fe(110)(2 × 2)‐O slab. Adsorbate DFT‐PDOS were also computed for Fe(110) ‐S. As, similar to adsorbed O, there is a significant continuous distribution of states about the Fermi level, it is proposed that the S 2p XPS core levels should also have asymmetric profiles. S 2p XPS data acquired from Fe(110) ‐S, and their subsequent fitting, verify this prediction, suggesting that DFT‐PDOS could aid line shape selection.

中文翻译：

---

核心能级光发射谱线的形状选择：铁上的原子吸附物

可靠地拟合核心能级光发射光谱对于X射线光电子能谱（XPS）数据的可靠解释通常至关重要。一个关键要素是为每个光谱分量采用正确的线形函数。在这项研究中，我们考虑了这个主题，重点研究了Fe（110）上原子吸附物（即O和S）的XPS数据。探索使用密度泛函理论（DFT）生成吸附物投影电子态密度（PDOS）以支持线形选择的潜力。从化学吸附的O的各种有序叠加器获得的O 1s核心能级XPS光谱均显示等效的不对称线形。先前的工作表明，这种不对称是费米能级附近有限O PDOS的结果，允许O 1s光激发通过电子-空穴对激发诱导最终状态的加权连续谱。为优化的五层Fe（110）（2×2）-O平板生成的O DFT-PDOS证实了这一起源。还计算了Fe（110）的吸附物DFT-PDOS -S。由于与吸附的O相似，费米能级附近存在显着的状态连续分布，因此建议S 2p XPS核心能级也应具有不对称分布。从Fe（110）-S获得的S 2p XPS数据 及其后续拟合证明了这一预测，表明DFT-PDOS可以帮助线形选择。