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arXiv physics/0506186physics.chem-phphysics.atom-ph
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关联能作为单粒子密度矩阵的显式泛函

The correlation energy as an explicit functional of the one-particle density matrix from a determinantal reference state

James Finley

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摘要：

利用基于多体微扰理论的方法，将关联能$\cEco$表示为$ρ_1$、$v$和$v_s$的显式泛函，其中$ρ_1$是来自非相互作用或参考定态的单粒子密度矩阵，$v$是来自相互作用或靶态的外势，$\cEco$是来自靶态的外势，$v_s$是来自靶态的外势，$\cEco$是来自靶态的外势。$v_s$是来自非相互作用决定态的外部势（的核）。换句话说，我们有$\cEco[ρ_1,v,v_s]$。另一种可能性是以下显式泛函：$\cEco[ρ_1,v_{\text{co}},v_s]$，其中$v_{\text{co}}$是来自非相互作用汉密尔顿的相关势（的核）。所提出的方法可以，在原则上，被用来计算$\cEco$在一个非常准确和有效的方式，因为，像Kohn-Sham的方法，没有虚拟轨道考虑。然而，与Kohn-Sham方法相反，$\cEco$是已知的、明确的泛函，其可以以系统的方式近似。为了简单起见，我们只考虑非相互作用的闭壳层态和非简并的单重基态的目标态;因此，在这种情况下，$ρ_1$表示来自决定性参考态的无自旋单粒子密度矩阵。

英文摘要：

Using an approach based on many body perturbation theory, the correlation energy $\cEco$ is expressed as an explicit functional of $ρ_1$, $v$, and $v_s$, where $ρ_1$ is the one-particle density matrix from the noninteracting, or reference, determinantal-state; $v$ is the external potential from the interacting, or target, state; $v_s$ is the (kernel of the) external potential from the noninteracting determinantal-state. In other words we have $\cEco[ρ_1,v,v_s]$. Anther possibility is the following explicit functional: $\cEco[ρ_1,v_{\text{co}},v_s]$, where $v_{\text{co}}$ is the (kernel of the) correlation potential from the noninteracting Hamiltonian. The proposed method can, in principle, be used to compute $\cEco$ in a very accurate and efficient manner, since, like the Kohn--Sham approach, there are no virtual orbitals to consider. However, in contrast to the Kohn--Sham approach, $\cEco$ is a known, explicit functional that can be approximated in a systematic manner. For simplicity, we only consider noninteracting closed-shell states and target states that are nondegenerate, singlet ground-states; so, in that case, $ρ_1$ denotes the spin-less one-particle density matrix from the determinantal reference state.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

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