ABSTRACT

XPS analyses of open shell ionic compounds, especially oxides of the first row transition metals, for information such as oxidation state tend to focus on characteristics of the metal 2p XPS features alone. These analyses could be made considerably more robust with simultaneous characterization of the XPS of the metal 3p features as well as the 2p features. In these comments, we provide a perspective on the conceptual and theoretical framework needed to extract chemical information from the complex multiplet structure of the 3p XPS of Fe oxides as representative of 3d transition metal oxides. We also present information about a novel kind of many-body effects that may contribute to a further redistribution of the Fe 3p XPS intensity. The concern here is not to develop a complicated mathematical formalism but to explain the complexity in terms of fundamental quantum mechanical concepts. This is done on the basis of ab initio Dirac Hartree–Fock wavefunctions where we examine the physical nature of the 3p XPS features of the representative ferrous and ferric oxides of FeO and Fe₂O₃, respectively. The key objectives of this paper are as follows: (1) to demonstrate the importance of the angular momentum coupling of open shell electrons, which is done more easily with RS multiplets; (2) to show that a single configuration description of the final state multiplets is woefully inadequate; (3) to identify a novel atomic many-body effect that can lead to a rich satellite structure. The considerations discussed here should have implications for making useful interpretations of the XPS of lower BE levels of other ionic, high spin materials. This paper provides a manifestation of a new tradition by which Comments on Inorganic Chemistry starts publishing original research content that, nonetheless, preserves the Journal’s identity as a niche for critical discussion of contemporary literature in inorganic chemistry; for previous manifestations, see Comments Inorg. Chem. 2020, 40, 277–303 and references cited in the abstract thereof.

摘要

开壳离子化合物的 XPS 分析，尤其是第一行过渡金属的氧化物，对于氧化态等信息，往往只关注金属 2p XPS 特征的特性。通过同时表征金属 3p 特征和 2p 特征的 XPS，可以使这些分析更加稳健。在这些评论中，我们提供了从作为 3d 过渡金属氧化物代表的 Fe 氧化物的 3p XPS 的复杂多重结构中提取化学信息所需的概念和理论框架的观点。我们还提供了有关可能有助于进一步重新分配 Fe 3p XPS 强度的新型多体效应的信息。这里关注的不是发展复杂的数学形式，而是解释基本量子力学概念的复杂性。这是基于从头开始Dirac Hartree-Fock 波函数，我们在其中检查 FeO 和 Fe ₂ O ₃的代表性氧化亚铁和氧化铁的 3p XPS 特征的物理性质， 分别。本文的主要目标如下： (1) 证明开壳电子角动量耦合的重要性，这更容易用 RS 多重态完成；(2) 表明最终状态多重态的单一构型描述严重不足；(3) 确定一种新的原子多体效应，可以导致丰富的卫星结构。此处讨论的考虑因素应有助于对其他离子高自旋材料的较低 BE 水平的 XPS 做出有用的解释。本文提供了一种新传统的体现，即评论无机化学开始发表原创研究内容，尽管如此，仍保留了该期刊作为对无机化学当代文献进行批判性讨论的利基市场的身份；对于以前的表现形式，请参阅评论 Inorg。化学。2020 , 40 , 277-303 及其摘要中引用的参考文献。