A two-density approach to the general many-body problem and a proof of principle for small atoms and molecules
Thomas Pope1(), Werner Hofer1,2
1. School of Natural and Environmental Sciences, Newcastle University, Newcastle NE1 7RU, United Kingdom 2. Institute of Physics & University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
An extended electron model fully recovers many of the experimental results of quantum mechanics while it avoids many of the pitfalls and remains generally free of paradoxes. The formulation of the manybody electronic problem here resembles the Kohn–Sham formulation of standard density functional theory. However, rather than referring electronic properties to a large set of single electron orbitals, the extended electron model uses only mass density and field components, leading to a substantial increase in computational efficiency. To date, the Hohenberg–Kohn theorems have not been proved for a model of this type, nor has a universal energy functional been presented. In this paper, we address these problems and show that the Hohenberg–Kohn theorems do also hold for a density model of this type. We then present a proof-of-concept practical implementation of this method and show that it reproduces the accuracy of more widely used methods on a test-set of small atomic systems, thus paving the way for the development of fast, efficient and accurate codes on this basis.
. [J]. Frontiers of Physics, 2019, 14(2): 23604.
Thomas Pope, Werner Hofer. A two-density approach to the general many-body problem and a proof of principle for small atoms and molecules. Front. Phys. , 2019, 14(2): 23604.
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