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arXiv · 2207.04169

Extending density functional theory with near chemical accuracy beyond pure water

Suhwan Song·Stefan Vuckovic·Youngsam Kim·Hayoung Yu·Eunji Sim·Kieron Burke
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Abstract

Density functional simulations of condensed phase water are typically inaccurate, due to the inaccuracies of approximate functionals. A recent breakthrough showed that the SCAN approximation can yield chemical accuracy for pure water in all its phases, but only when its density is corrected. This is a crucial step toward first-principles biosimulations. However, weak dispersion forces are ubiquitous and play a key role in noncovalent interactions among biomolecules, but are not included in the new approach. Moreover, na\"ive inclusion of dispersion in HF-SCAN ruins its high accuracy for pure water. Systematic application of the principles of density-corrected DFT yields a functional (HF-r$^2$SCAN-DC4) which recovers and not only improves over HF-SCAN for pure water, but also captures vital noncovalent interactions in biomolecules, making it suitable for simulations of solutions.

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Suhwan Song, Stefan Vuckovic, Youngsam Kim, Hayoung Yu, Eunji Sim, Kieron Burke. 2022-07-09. Extending density functional theory with near chemical accuracy beyond pure water. https://arxiv.org/abs/2207.04169

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