The inverse Kohn-Sham density-functional theory (inv-KS) for the electron density of the Hartree-Fock (HF) wave function was revisited within the context of the optimized effective potential (HF- OEP). First, it is proved that the exchange potential created by the inv-KS is equivalent to the potential obtained by the HF-OEP when the HF-OEP realizes the HF energy of the system under consideration. Next the real-space grid (RSG) implementations of the inv-KS and the HF-OEP are addressed. The total HF energies EHF for the wave functions on the effective potentials optimized by the inv-KS are computed for a set of small molecules. It is found that the mean absolute deviation (MAD) of EHF from the HF energy is clearly smaller than the MAD of EHF, demonstrating that the inv-KS is advantageous in constructing the detailed structure of the exchange potential vx as compared with the HF-OEP. The inv-KS method is also applied to an ortho-benzyne radical known as a strongly correlated polyatomic molecule. It is revealed that the spin populations on the atomic sites computed by the UHF calculation can be faithfully reproduced by the wave functions on the inv-KS potential.
Computing X-ray absorption spectra from linear-response particles atop optimized holes
状态特定轨道优化密度泛函理论（OO-DFT）方法如限制性开壳层Kohn-Sham（ROKS）方法可以半定量地预测闭壳层分子的X射线吸收光谱。然而，OO-DFT方法要求每个状态被单独优化。在这项工作中，我们提出了一种方法来产生一个近似的核心激发态密度使用的ROKS能量分析，这是能够提供合理的准确性，而不需要特定的状态优化。这是通过完全优化的核心-空穴通过核心电离状态，然后通过使用电子添加配置相互作用单打（EA-CIS），以获得粒子的水平。这种混合方法可以被看作是静态交换（STEX）方法的DFT推广，并可以通过使用PBE和OLYP等局部泛函来获得C-F的K边的$\sim 0.6$ eV RMS误差。这种ROKS（STEX）方法也可以用来识别重要的转变，为全OO ROKS处理，因此可以帮助减少计算成本，获得OO-DFT质量的频谱。因此，ROKS（STEX）似乎是一种有效的预测X射线吸收光谱的有用技术。
Faster Exact Exchange for Solids via occ-RI-K: Application to Combinatorially Optimized Range-Separated Hybrid Functionals for Simple Solids with Pseudopotentials Near the Basis Set Limit
In this work, we developed and showcased the occ-RI-K algorithm to compute the exact exchange contribution in density functional calculations of solids near the basis set limit. Within the gaussian planewave (GPW) density fitting, our algorithm achieves a 1-2 orders of magnitude speedup compared to conventional GPW algorithms. Since our algorithm is well-suited for simulations with large basis sets, we applied it to 12 hybrid density functionals with pseudopotentials and a large uncontracted basis set to assess their performance on band gaps of 25 simple solids near the basis set limit. The la…
Adaptive Expansions of the Optimized Effective Potential in Physically Motivated Response Spaces
Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń（托伦哥白尼大学物理、天文学与信息学学院物理研究所）；Institute of Advanced Studies, Nicolaus Copernicus University in Toruń（托伦哥白尼大学高等研究院）
Self-consistent double-hybrid density-functional theory using the optimized-effective-potential method
我们介绍了一个轨道优化的双杂交（DH）计划使用优化有效势（OEP）方法。使用对应于完整的交换相关能量表达式的局部势优化轨道，包括二阶M{\displaystyle M {\math}ller-Plesset（MP2）相关贡献。我们已经实现了一个单参数版本的基于OEP的自洽DH计划使用BLYP密度泛函近似，并将其与相应的非自洽DH计划进行比较，用于计算一些闭壳层原子和分子。虽然基于OEP的自洽性并没有为基态总能量和电离势的计算提供任何改进，但它确实提高了电子亲和势的准确性，并恢复了LUMO轨道能量与中性激发能相关的含义。此外，基于OEP的自洽DH方案提供了相当准确的交换相关势和相关密度。
