论文标题
集合密度功能理论中局部交换相关功能的重量依赖性：双电子系统中的双重激发
Weight Dependence of Local Exchange-Correlation Functionals in Ensemble Density-Functional Theory: Double Excitations in Two-Electron Systems
论文作者
论文摘要
GROSS - oliveira-kohn（Gok）集合密度官能理论（GOK-DFT）是时间 - \ textIt {独立}密度官能理论（DFT）的延伸，可以通过集合能量的衍生能计算出激发态能量的集合能量，该衍生能与集合能量相对于整体权重。与DFT（TD-DFT）的时间相关版本相反，可以在Gok-DFT中轻松计算双激发。但是，要充分利用这种形式主义，必须访问\ textIt {weightipent}交换相关功能，以模拟臭名昭著的集合衍生物对兴奋能量的贡献。在本文中，我们讨论了针对两电子原子和分子系统（He and H $ _2 $）的首发（即局部）重量依赖性交换密度功能函数近似的构建。本着最佳调整范围分离的混合功能的精神，提出了一个两步系统依赖的程序来获得与双激发相关的准确能量。
Gross--Oliveira--Kohn (GOK) ensemble density-functional theory (GOK-DFT) is a time-\textit{independent} extension of density-functional theory (DFT) which allows to compute excited-state energies via the derivatives of the ensemble energy with respect to the ensemble weights. Contrary to the time-dependent version of DFT (TD-DFT), double excitations can be easily computed within GOK-DFT. However, to take full advantage of this formalism, one must have access to a \textit{weight-dependent} exchange-correlation functional in order to model the infamous ensemble derivative contribution to the excitation energies. In the present article, we discuss the construction of first-rung (i.e., local) weight-dependent exchange-correlation density-functional approximations for two-electron atomic and molecular systems (He and H$_2$) specifically designed for the computation of double excitations within GOK-DFT. In the spirit of optimally-tuned range-separated hybrid functionals, a two-step system-dependent procedure is proposed to obtain accurate energies associated with double excitations.
