• Corpus ID: 220961431

How errors in densities contaminate empirical density functionals

@article{Song2020HowEI,
  title={How errors in densities contaminate empirical density functionals},
  author={Suhwan Song and Eunji Sim and Stefan Vuckovic and Kieron Burke},
  journal={arXiv: Chemical Physics},
  year={2020}
}
Empirical fitting of parameters in approximate density functionals is commonplace. Such database fits conflate errors in the self-consistent density with errors in the energy functional, but density-corrected DFT (DC-DFT) separates these two. Three examples both show the pitfalls and how they can be avoided: Catastrophic failures in a toy example, $H_2^+$ at varying bond lengths, where the standard fitting procedure misses the exact functional; Grimme's D3 fit to noncovalent interactions, which… 

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