The covalent character of the interaction between the metal cation and the oxygen ligands has been examined for two Fe oxides with different nominal oxidation states, Fe(II)O, and Fe(III)₂O₃. The covalent character is examined for the initial, ground state configuration and for the ionic states involving the removal of a shallow core, Fe 3p, and a deep core, Fe 2p, electron. The covalency is assessed based on novel theoretical analyses of wave functions for the various cases. It is found that the covalency is considerably different for different oxidation states and for different ionized and non-ionized configurations. The changes in covalency for the ions are shown to be responsible for important changes in relaxation energies for X-Ray Photoelectron Spectroscopy (XPS) spectra and in the intensity lost from main XPS peaks to shake satellites. While these consequences are not observables themselves, they are important for the interpretation of the XPS spectra, in particular, for efforts to extract stoichiometries of these iron oxides from XPS data. This is a finding likely applicable across various 3d transition metal oxide materials.

中文翻译：

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Fe2O3和FeO的共价性：XPS卫星强度的后果

对于具有不同标称氧化态的两种Fe氧化物Fe（II）O和Fe（III）₂ O ₃，已经研究了金属阳离子与氧配体之间相互作用的共价特性。。检查了共价特性的初始基态构型和离子态，包括去除了浅核Fe 3p和深核Fe 2p电子。基于对各种情况的波动函数的新颖理论分析，评估了其等效性。已经发现，对于不同的氧化态以及不同的电离和非电离构型，共价显着不同。离子的共价变化表明是X射线光电子能谱（XPS）光谱弛豫能的重要变化以及从XPS主峰到摇动卫星损失的强度的重要原因。虽然这些后果本身是无法观察到的，但它们对于XPS光谱的解释尤其重要，从XPS数据中提取这些氧化铁的化学计量的方法。这一发现可能适用于各种3d过渡金属氧化物材料。