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arXiv · 2309.10390

A density-fitting implementation of the density-based basis-set correction method

Andreas Heßelmann·Emmanuel Giner·Peter Reinhardt·Peter J. Knowles·Hans-Joachim Werner·Julien Toulouse
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Abstract

This work reports an efficient density-fitting implementation of the density-based basis-set correction (DBBSC) method in the MOLPRO software. This method consists in correcting the energy calculated by a wave-function method with a given basis set by an adapted basis-set correction density functional incorporating the short-range electron correlation effects missing in the basis set, resulting in an accelerated convergence to the complete-basis-set limit. Different basis-set correction density-functional approximations are explored and the complementary-auxiliary-basis-set single-excitation correction is added. The method is tested on a benchmark set of reaction energies at the second-order Møller-Plesset (MP2) level and a comparison with the explicitly correlated MP2-F12 method is provided. The results show that the DBBSC method greatly accelerates the basis convergence of MP2 reaction energies, without reaching the accuracy of the MP2-F12 method but with a lower computational cost.

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Andreas Heßelmann, Emmanuel Giner, Peter Reinhardt, Peter J. Knowles, Hans-Joachim Werner, Julien Toulouse. 2024-02-19. A density-fitting implementation of the density-based basis-set correction method. https://doi.org/10.1002/jcc.27325

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