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arXiv · 2301.12308

Correcting models with long-range electron interaction using generalized cusp conditions

Andreas Savin·Jacek Karwowski
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Abstract

Sources of energy errors resulting from the replacement of the physical Coulomb interaction by its long-range $\mathrm{erfc}(\mu r)/r$ approximation are explored. It is demonstrated that the results can be dramatically improved and the range of $\mu$ giving energies within chemical accuracy limits significantly extended, if the generalized cusp conditions are used to represent the wave function at small $r$. The numerical results for two-electron harmonium are presented and discussed.

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Andreas Savin, Jacek Karwowski. 2023-01-28. Correcting models with long-range electron interaction using generalized cusp conditions. https://doi.org/10.1021/acs.jpca.2c08426

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