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arXiv · 2411.01526

Accelerating Fock build via hybrid analytical-numerical integration

Yong Zhang·Rongding Lei·Bingbing Suo·Wenjian Liu
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Abstract

A very robust and efficient hybrid analytic-numerical Fock build, aMECP+aCOSx, has been developed for accelerating HF/DFT calculations. The essential idea is to extract those portions of the Fock matrix that can readily be evaluated analytically, so as to minimize numerical noises arising from the semi-numerical and numerical integrations. As a result, the combination of aMECP with a medium grid and aCOSx with a coarse grid is already sufficient to achieve an accuracy of less than 1{\mu}Eh/atom in total energies. The acceleration of aMECP+aCOSx over the analytic Fock build is already seen in calculations of small molecular systems and is more enhanced in calculations of large molecules with extended basis sets.

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Yong Zhang, Rongding Lei, Bingbing Suo, Wenjian Liu. 2024-11-03. Accelerating Fock build via hybrid analytical-numerical integration. https://arxiv.org/abs/2411.01526

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