论文标题
集合密度功能理论中的个体相关性：国家驱动/密度驱动的分解，而没有其他Kohn-Sham系统
Individual correlations in ensemble density-functional theory: State-driven/density-driven decompositions without additional Kohn-Sham systems
论文作者
论文摘要
古尔德和皮塔利斯[物理学。莱特牧师。 123，016401（2019）]最近揭示了密度驱动的（DD）相关能量，该能量特定于许多电子集合，必须通过近似值来解释。我们在这封信中得出了整体权重，集合Kohn-Sham（KS）轨道的一般性和简单表达，以及它们对集合权重的变化的线性响应。由于不需要额外的州驱动KS系统，因此大大简化了其评估。我们确认了DD效应的重要性，并引入了近似值的直接和有希望的途径。
Gould and Pittalis [Phys. Rev. Lett. 123, 016401 (2019)] recently revealed a density-driven (DD) correlation energy that is specific to many-electron ensembles and must be accounted for by approximations. We derive in this Letter a general and simpler expression in terms of the ensemble weights, the ensemble Kohn-Sham (KS) orbitals, and their linear response to variations in the ensemble weights. As no additional state-driven KS systems are needed, its evaluation is greatly simplified. We confirm the importance of DD effects and introduce a direct and promising route to approximations.
