Iterative charge equilibration for fourth-generation high-dimensional neural network potentials
- Author(s)
- Emir Kocer, Andreas Singraber, Jonas A. Finkler, Philipp Misof, Tsz Wai Ko, Christoph Dellago, Jörg Behler
- Abstract
Machine learning potentials allow performing large-scale molecular dynamics simulations with about the same accuracy as electronic structure calculations, provided that the selected model is able to capture the relevant physics of the system. For systems exhibiting long-range charge transfer, fourth-generation machine learning potentials need to be used, which take global information about the system and electrostatic interactions into account. This can be achieved in a charge equilibration step, but the direct solution of the set of linear equations results in an unfavorable cubic scaling with system size, making this step computationally demanding for large systems. In this work, we propose an alternative approach that is based on the iterative solution of the charge equilibration problem (iQEq) to determine the atomic partial charges. We have implemented the iQEq method, which scales quadratically with system size, in the parallel molecular dynamics software LAMMPS for the example of a fourth-generation high-dimensional neural network potential (4G-HDNNP) intended to be used in combination with the n2p2 library. The method itself is general and applicable to many different types of fourth-generation MLPs. An assessment of the accuracy and the efficiency is presented for a benchmark system of FeCl3 in water.
- Organisation(s)
- Computational and Soft Matter Physics
- External organisation(s)
- Ruhr-Universität Bochum (RUB), Aalborg University (AAU), University of Vienna, University of California, San Diego
- Journal
- Journal of Chemical Physics
- Volume
- 162
- No. of pages
- 12
- ISSN
- 0021-9606
- DOI
- https://doi.org/10.48550/arXiv.2502.07907
- Publication date
- 03-2025
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103015 Condensed matter, 102019 Machine learning, 104022 Theoretical chemistry
- ASJC Scopus subject areas
- General Physics and Astronomy, Physical and Theoretical Chemistry
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/e796426d-3a5d-4f4b-8bdc-5949dfc3cfcc