Increasing the applicability of density functional theory. III. Do consistent Kohn-Sham density functional methods exist?
Increasing the applicability of density functional theory. III. Do consistent Kohn-Sham density functional methods exist?
复制标题
增加密度泛函理论的适用性。
DOI：
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发表时间：
2012
影响因子：
4.4
通讯作者：
R. Bartlett
中科院分区：
文献类型：
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作者：
P. Verma;R. Bartlett
讨论了“一致的”Kohn-Sham （KS）密度泛函理论（DFT）的概念，其中泛函能够提供良好的总能量，其自洽势使得KS特征值对应于分子的主电离势的精确近似。今天，大量的DFT近似中没有一个显示出这个性质。唯一的例外是建立在交换和关联的最优有效势策略上的从头算dft方法。这是一种DFT方法，因为它将相关密度表示为单个行列式，并且通过施加该条件，生成用于轨道和特征值自洽解的局部交换和相关算符。这种“一致”DFT具有戴森方程的许多特性，但没有其频率依赖性和相关的复杂性。讨论了基于MBPT2泛函的从头算dft与GW方法之间的关系。从头算dft提供了一种具有局部相关势的自洽、频率无关、有效的独立粒子替代。
The concept of a "consistent," Kohn-Sham (KS) density functional theory (DFT) is discussed, where the functional is able to provide good total energies and its self-consistent potential is such that the KS eigenvalues correspond to accurate approximations to the principal ionization potentials for the molecule. Today, none of the vast number of DFT approximations show this property. The one exception is the ab initio dft method built upon the optimized effective potential strategy for exchange and correlation. This qualifies as a DFT method because it represents the correlated density as a single determinant and by imposing that condition, generates local exchange and correlation operators which are used in self-consistent solutions of the orbitals and eigenvalues. Such a "consistent" DFT shares many of the properties of the Dyson equation, but without its frequency dependence and associated complications. The relationship between ab initio dft based on MBPT2 functional and GW method is discussed. Ab initio dft provides a self-consistent, frequency independent, effective independent particle alternative with a local correlation potential.