Kohn-Sham density functional theory calculations of non-resonant and resonant x-ray emission spectroscopy
Kohn-Sham density functional theory calculations of non-resonant and resonant x-ray emission spectroscopy
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DOI：
10.1063/1.4977178
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发表时间：
2017-03-07
影响因子：
4.4
通讯作者：
Besley, Nicholas A.
中科院分区：
文献类型：
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作者：
Hanson-Heine, Magnus W. D.;George, Michael W.;Besley, Nicholas A.
对基于Kohn-Sham密度泛函理论模拟的非共振和共振(共振非弹性X射线散射)X射线发射谱的精度进行了评估。当使用为计算X射线吸收光谱而设计的短程修正交换相关泛函时，得到了具有正确能量标度的准确的非共振X射线发射光谱。结果表明，通过使用描述核激发态的参考行列式，该方法可以扩展到模拟共振非弹性X射线散射。对于这种光谱，发现标准的杂化泛函B3LYP给出了准确的光谱，再现了在实验中观察到的特征。然而，正确描述不同中间态引起的光谱的细微变化的能力更具挑战性，需要从分子动力学模拟中平均构象。总之，证明了用Kohn-Sham密度泛函理论可以直接模拟准确的非共振和共振X射线发射光谱。(C)2017年作者(S)。除另有说明外，所有文章内容均受知识共享署名(CC BY)许可。
The accuracy of non-resonant and resonant (resonant inelastic X-ray scattering) X-ray emission spectra simulated based upon Kohn-Sham density functional theory is assessed. Accurate non-resonant X-ray emission spectra with the correct energy scale are obtained when short-range corrected exchange-correlation functionals designed for the calculation of X-ray absorption spectroscopy are used. It is shown that this approach can be extended to simulate resonant inelastic X-ray scattering by using a reference determinant that describes a core-excited state. For this spectroscopy, it is found that a standard hybrid functional, B3LYP, gives accurate spectra that reproduce the features observed in experiment. However, the ability to correctly describe subtle changes in the spectra arising from different intermediate states is more challenging and requires averaging over conformations from a molecular dynamics simulation. Overall, it is demonstrated that accurate non-resonant and resonant X-ray emission spectra can be simulated directly from Kohn-Sham density functional theory. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license.