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arXiv · 1608.02553

Exact Exchange-Correlation Functional for the Infinitely Stretched Hydrogen Molecule

Eduard Matito·David Casanova·Xabier Lopez·Jesus M. Ugalde
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Abstract

The exchange-correlation hole density of the infinitely stretched (dissociated) hydrogen molecule can be cast into a closed analytical form by using its exact wave function. This permits to obtain an explicit exchange-correlation energy functional of the electron density which allows for its functional derivation to yield the corresponding Kohh-Sham effective exchange-correlation potential. We have shown that this exchange-correlation functional is exact for the dissociated hydrogen molecule, yields its dissociation energy correctly, and its corresponding exchange-correlation potential has the correct $-1/r$ asymptotic behavior.

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Eduard Matito, David Casanova, Xabier Lopez, Jesus M. Ugalde. 2016-08-08. Exact Exchange-Correlation Functional for the Infinitely Stretched Hydrogen Molecule. https://doi.org/10.1007/s00214-016-1982-x

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