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arXiv · 2507.09814

DLPNO-MP2 for Periodic Systems using Megacell Embedding

Andrew Zhu·Arman Nejad·Poramas Komonvasee·Kesha Sorathia·David P. Tew
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Abstract

We present a domain-based local pair natural orbital M{\o}ller--Plesset second order perturbation theory (DLPNO-MP2) for periodic systems, working within an LCAO formalism within the Tubromole program package. This approach, Megacell-DLPNO-MP2, embeds a supercell correlation treatment within a megacell and does not involve periodic image summation for the Coulomb integrals. Working in a basis of well-localised Wannier functions, periodicity is instead imposed through rigorous translational symmetry of Hamiltonian integrals and wavefunction parameters. The accuracy of the method is validated through comparison with a complementary periodic DLPNO-MP2 method that employs Born--von K{\'a}rm{\'a}n boundary conditions, described in paper I of this series. The PNO approximations are shown to be equivalent in the two approaches and entirely consistent with molecular DLPNO-MP2 calculations. The Megacell-DLPNO-MP2 method displays sub-linear scaling with respect to supercell size at the asymptotic limit and example calculations are presented with up to 15000 basis functions in the correlation treatment.

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Andrew Zhu, Arman Nejad, Poramas Komonvasee, Kesha Sorathia, David P. Tew. 2025-07-13. DLPNO-MP2 for Periodic Systems using Megacell Embedding. https://arxiv.org/abs/2507.09814

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