Tackling the Peak Assignment Problem in X-ray Photoelectron Spectroscopy with First Principles Calculations

x射线光电子能谱（XPS）是应用表面科学中应用最广泛的表征方法之一。它被应用于多相催化、环境降解、腐蚀、表面涂层的制造和各种其他过程的研究。然而，XPS测量的实际价值目前受到记录光谱分析中普遍存在的问题的负面影响。在最近的科学文献中对这些问题进行了广泛的讨论，并且在核心水平XPS中峰拟合和峰分配问题已被确定为XPS光谱分析中显着误差的来源。这些问题可能会限制XPS能够提供的有用化学信息的数量，而且，不正确的峰分配可能导致对潜在化学物质得出错误的结论。本研究项目的目的是通过支持和鼓励在实验XPS光谱解释中更广泛地使用计算方法来解决这些问题，从而使XPS成为更可靠和更有用的表征方法。具体来说，我们希望使现有的计算核心电子结合能和模拟核心能级谱的计算方法可供更广泛的研究人员使用，并对这些方法进行改进，使它们能够更好地满足XPS用户的需求。我们将开发新的、计算效率高、用户友好的delta-SCF方法和GW+累积方法的实现，开展案例研究，旨在测试当前理论在指导现实世界光谱分析方面的局限性，并组织研讨会和编写教程，以增加计算技术的用户基础。计划中的工作将由理论光谱学专家、电子结构代码开发人员、XPS用户和仪器制造商组成的国际、跨学科和跨部门团队进行

X-ray Photoelectron Spectroscopy (XPS) is one of the most widely used methods of characterization in applied surface science. It is applied in studies of heterogeneous catalysis, environmental degradation, corrosion, the manufacture of surface coatings, and various other processes. However, the practical value of XPS measurements is currently negatively affected by widespread problems in the analysis of recorded spectra. These have been extensively discussed in recent scientific literature, and problems with peak fitting and peak assignment in core level XPS have been identified as a source of significant errors in the analysis of XPS spectra. These problems can limit the amount of useful chemical insights that XPS is able to provide, and moreover, incorrect peak assignments can lead to the wrong conclusions being drawn about the underlying chemistry. The aim of this research project is to tackle these problems by enabling and encouraging the more widespread use of computational methods in the interpretation of experimental XPS spectra, and to thereby make XPS a more reliable and more useful method of characterization. Specifically, we want to make existing computational methods for calculating core electron binding energies and simulating core level spectra accessible to a wider community of researchers, and to improve these methods such that they would better meet the needs of XPS users. We will develop new, computationally efficient and user-friendly implementations of the delta-SCF method and the GW+cumulant approach, carry out case-studies that are designed to test the limits of current theories in guiding the analysis of real world spectra, and organize workshops and write tutorials to increase the user base of the computational techniques. The planned work will be carried out by an international, interdisciplinary and intersectoral team of experts in theoretical spectroscopy, developers of electronic structure codes, XPS users, and instrument manufacturers