Liu Liping, Xu Qiang, Dos Anjos Cunha Leonardo, Xin Hongliang, Head-Gordon Martin, Qian Jin
Department of Chemical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060, United States.
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
J Chem Theory Comput. 2024 Jul 23;20(14):6134-6143. doi: 10.1021/acs.jctc.4c00535. Epub 2024 Jul 5.
X-ray photoelectron spectroscopy (XPS) is a powerful characterization technique that unveils subtle chemical environment differences via core-electron binding energy (CEBE) analysis. We extend the development of real-space pseudopotential methods to calculating 1s, 2s, and 2p CEBEs of third-row elements (S, P, and Si) within the framework of Kohn-Sham density-functional theory (KS-DFT). The new approach systematically prevents variational collapse and simplifies core-excited orbital selection within dense energy level distributions. However, careful error cancellation analysis is required to achieve accuracy comparable to all-electron methods and experiments. Combined with real-space KS-DFT implementation, this development enables large-scale simulations with both Dirichlet boundary conditions and periodic boundary conditions.
X射线光电子能谱（XPS）是一种强大的表征技术，它通过芯电子结合能（CEBE）分析揭示细微的化学环境差异。我们将实空间赝势方法的发展扩展到在Kohn-Sham密度泛函理论（KS-DFT）框架内计算第三周期元素（S、P和Si）的1s、2s和2p CEBE。这种新方法系统地防止了变分坍缩，并简化了密集能级分布内的芯激发轨道选择。然而，需要进行仔细的误差抵消分析，以达到与全电子方法和实验相当的精度。结合实空间KS-DFT实现，这一发展使得能够在狄利克雷边界条件和周期边界条件下进行大规模模拟。
