Lattice density-functional theory for quantum chemistry
Lattice density-functional theory for quantum chemistry
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用于量子化学的晶格密度泛函理论
DOI：
10.1103/physrevb.99.165118
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发表时间：
2019-02
影响因子：
3.7
通讯作者：
J. P. Coe
中科院分区：
文献类型：
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作者：
J. P. Coe
我们提出了一种用于从头算量子化学或物理学的晶格密度泛函理论，作为一种有效方法的途径，该方法可以近似具有强相关电子的分子的完整构型相互作用能和轨道占据。我们以哈伯德模型的晶格密度泛函理论为基础，推导了简化后的全量子化学哈密顿量的 Kohn-Sham 方程，并在势能曲线上演示了该方法，用于解决六个氢原子线性链中伸长键建模的挑战性问题。这里测试了该量子化学系统的 Bethe-ansatz 局域密度近似的准确性，我们发现，尽管该近似函数是为 Hubbard 模型设计的，但势曲线的形状通常与完整构型相互作用结果一致。尽管非常拉伸的键存在差异，但该差异低于使用标准密度泛函理论和局域密度近似时的差异。
We propose a lattice density-functional theory for ab initio quantum chemistry or physics as a route to an efficient approach that approximates the full configuration interaction energy and orbital occupations for molecules with strongly correlated electrons. We build on lattice density-functional theory for the Hubbard model by deriving Kohn-Sham equations for a reduced then full quantum chemistry Hamiltonian and demonstrate the method on the potential energy curves for the challenging problem of modeling elongating bonds in a linear chain of six hydrogen atoms. Here the accuracy of the Bethe-ansatz local-density approximation is tested for this quantum chemistry system, and we find that, despite this approximate functional being designed for the Hubbard model, the shapes of the potential curves generally agree with the full configuration interaction results. Although there is a discrepancy for very stretched bonds, it is lower than when using standard density-functional theory with the local-density approximation.