SALTED: a symmetry-adapted machine-learning program for predicting electron-densities in molecules and materials

arXiv (Cornell University)

Abstract

SALTED provides an open-source Python package for machine learning the quantum-mechanical electron density, $n(\mathbf{r})$, in molecular and condensed-phase systems based on input atomic coordinates and species. The program adopts a linear atom-centered decomposition of the electron density, which makes it highly transferable across diverse atomistic configurations sharing similar chemical environments. Because of this representation choice, SALTED is naturally interfaced with state-of-the-art electronic-structure programs based on atomic orbitals, namely CP2K, FHI-aims, and PySCF, from which reference electron-density data can be generated and used to train a model. The learning algorithm is based on a symmetry-adapted extension of Gaussian process regression, making SALTED especially efficient in small-data regimes. Thanks to the implementation of vector-field kernel functions, SALTED can also learn the first-order response of the electron density to applied electric fields, $\partial n(\mathbf{r})/\partial \mathbf{E}$. The application of SALTED within computational workflows has already shown its utility in a wide variety of contexts, including the calculation of polarization vectors and polarizability tensors, the accurate evaluation of Coulomb forces in QM/MM molecular-dynamics simulations, and electronic-structure studies of large-scale 2D materials.

Authors 8

1. Zekun Lou

   Max Planck Institute for the Structure and Dynamics of Matter

   Affiliation as printed

   MPI for the Structure and Dynamics of Matter , Hamburg , Germany

2. Alan M. Lewis

   University of York

   Affiliation as printed

   Department of Chemistry , University of York , York , UK

3. T. Bernhard

   Centre National de la Recherche Scientifique · Sorbonne Université · PHENIX laboratory

   Affiliation as printed

   Physicochimie des Électrolytes et Nanosystèmes Interfaciaux , Sorbonne Université , CNRS , F-75005 Paris , France

4. Lukas Seifert Aachen Institute of Inorganic Chemistry

   RWTH Aachen University

   Affiliation as printed

   Institute of Inorganic Chemistry , RWTH Aachen University , Landoltweg 1a , 52074 Aachen , Germany

5. Agustin Salcedo

   Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · École Normale Supérieure - PSL · Sorbonne Université · Laboratoire de Physique de l'Ecole Normale Supérieure

   Affiliation as printed

   Laboratoire de physique de L'École normale supérieure de Paris , CNRS , ENS & Université PSL , Sorbonne Université , Université de Paris , F-75005 Paris , France

6. Florian Kleemiss Aachen Institute of Inorganic Chemistry

   RWTH Aachen University

   Affiliation as printed

   Institute of Inorganic Chemistry , RWTH Aachen University , Landoltweg 1a , 52074 Aachen , Germany

7. Mariana Rossi

   University of Cambridge · Max Planck Institute for the Structure and Dynamics of Matter

   Affiliation as printed

   MPI for the Structure and Dynamics of Matter , Hamburg , Germany

   Yusuf Hamied Department of Chemistry , Cambridge University , Cambridge , UK

8. Andrea Grisafi

   Centre National de la Recherche Scientifique · Sorbonne Université · PHENIX laboratory

   Affiliation as printed

   Physicochimie des Électrolytes et Nanosystèmes Interfaciaux , Sorbonne Université , CNRS , F-75005 Paris , France