# The Hubbard dimer: a density functional case study of a many-body problem

@article{Carrascal2015TheHD, title={The Hubbard dimer: a density functional case study of a many-body problem}, author={Diego Carrascal and Jaime Ferrer and J. C. Smith and Kieron Burke}, journal={Journal of Physics: Condensed Matter}, year={2015}, volume={27} }

This review explains the relationship between density functional theory and strongly correlated models using the simplest possible example, the two-site Hubbard model. The relationship to traditional quantum chemistry is included. Even in this elementary example, where the exact ground-state energy and site occupations can be found analytically, there is much to be explained in terms of the underlying logic and aims of density functional theory. Although the usual solution is analytic, the…

## 81 Citations

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Abstract
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