论文标题
光谱密度功能理论的力矩电势：利用均匀电子气体的动量分布
Moment potentials for spectral density functional theory: Exploiting the momentum distribution of the uniform electron gas
论文作者
论文摘要
在标准的Kohn-Sham（KS）密度功能理论（DFT）中，Ni和Pd中的价带卫星缺失，Ni和Na中的带宽太大，并且不描述Srvo $ _3 $中的下层和上关重频段的形成。可以通过从前四个光谱矩构建光谱函数来纠正这些光谱特征，可以在\ textIt {基于矩函数的频谱密度函数理论}（MFBSDFT）中有效地获得数值获得。为了获得第二刻的合适潜力，可以使用均匀电子气体（UEG）的现有模型。但是，UEG第三时刻的模型尚不可用。因此，我们表明，在光谱函数的两极近似中重现UEG的动量分布决定了第二矩时的第三刻。这使我们能够找到第二和第三刻电势的模型，该模型重现了Ni，Pd，Na和Srvo $ _3 $的实验光谱，并且与低密度下UEG的第二刻一致。此外，我们描述了一种有效的算法来计算第一个$ 2p $频谱矩阵的光谱函数，该矩阵通过使用超过4个光谱矩来提高MFBSDFT的准确性铺平了道路。
In standard Kohn-Sham (KS) density-functional theory (DFT) the valence band satellites in Ni and Pd are missing, the band widths in Ni and Na are too large, and the formation of lower and upper Hubbard bands in SrVO$_3$ is not described. These spectral features may be corrected by constructing the spectral function from the first four spectral moments, which may be obtained numerically efficiently within a \textit{moment-functional based spectral density functional theory} (MFbSDFT). In order to obtain a suitable potential for the second moment, one may use existing models of the uniform electron gas (UEG). However, models for the third moment of the UEG are not yet available. Therefore, we show that reproducing the momentum distribution of the UEG within the two-pole approximation of the spectral function determines the third moment, when the second moment is given. This allows us to find a model for the second and third moment potentials, which reproduces the experimental spectra of Ni, Pd, Na, and SrVO$_3$, and which is consistent with the second moment of the UEG at low density. Additionally, we describe an efficient algorithm to compute the spectral function from the first $2P$ spectral moment matrices, which paves the way to increasing the accuracy of MFbSDFT by using more than 4 spectral moments.
