Simulating X-ray photoelectron spectra with strong electron correlation using multireference algebraic diagrammatic construction theory
Simulating X-ray photoelectron spectra with strong electron correlation using multireference algebraic diagrammatic construction theory
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DOI：
10.1039/d1cp05476g
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发表时间：
2022-01-27
影响因子：
3.3
通讯作者：
Sokolov, Alexander Yu
中科院分区：
文献类型：
--
作者：
de Moura, Carlos E., V;Sokolov, Alexander Yu
我们提出了一种新的理论方法，用于模拟强相关分子系统的X射线光电子能谱，该方法结合了多参考代数图解构造理论（MR-ADC）[J. Chem. Phys.，2018，149，204113]，使用核-价分离（CVS）技术。由此产生的CVS-MR-ADC方法具有较低的计算成本，同时克服了与计算内壳和核分子轨道的激发相关的传统多参考理论的许多挑战。我们的研究结果表明，CVS-MR-ADC方法是准确的单参考ADC近似预测弱相关分子的核心电离能，但更准确和可靠的系统与多参考字符，如拉伸氮分子，臭氧，和异构体的苯炔双自由基。我们还强调了多参考效应的重要性，用于确定强相关系统的XPS谱中峰的相对间距和顺序的核心孔筛选的描述。
We present a new theoretical approach for the simulations of X-ray photoelectron spectra of strongly correlated molecular systems that combines multireference algebraic diagrammatic construction theory (MR-ADC) [J. Chem. Phys., 2018, 149, 204113] with a core-valence separation (CVS) technique. The resulting CVS-MR-ADC approach has a low computational cost while overcoming many challenges of the conventional multireference theories associated with the calculations of excitations from inner-shell and core molecular orbitals. Our results demonstrate that the CVS-MR-ADC methods are as accurate as single-reference ADC approximations for predicting core ionization energies of weakly-correlated molecules, but are more accurate and reliable for systems with a multireference character, such as a stretched nitrogen molecule, ozone, and isomers of the benzyne diradical. We also highlight the importance of multireference effects for the description of core-hole screening that determines the relative spacing and order of peaks in the XPS spectra of strongly correlated systems.