Saved in:
Bibliographic Details
Main Authors: Labavić, Darka, Brünig, Florian N., Netz, Roland R., Bocquet, Marie-Laure, Berthoumieux, Hélène
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2505.11101
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918022193610752
author Labavić, Darka
Brünig, Florian N.
Netz, Roland R.
Bocquet, Marie-Laure
Berthoumieux, Hélène
author_facet Labavić, Darka
Brünig, Florian N.
Netz, Roland R.
Bocquet, Marie-Laure
Berthoumieux, Hélène
contents The nonlocal dielectric properties of liquid water are studied in the context of {\it ab initio} molecular dynamics simulations based on density functional theory. We calculate the dielectric response from the charge structure factor of the liquid using the fluctuation-dissipation theorem. We show that the dielectric response function of {\it ab initio} simulations differs significantly from that of classical force-fields, both qualitatively and quantitatively. In particular, it exhibits a larger amplitude and a wider range of responding wave numbers. We suggest that the difference is due to the localisation of the electronic charge density inherent in classical force files and Wannier post-treatment of DFT densities. The localised charge models do not reproduce the shape of the response function even for $q$ corresponding to intermolecular distances, and could lead to a significant underestimation of the dielectric response of the liquid by a factor of 10.
format Preprint
id arxiv_https___arxiv_org_abs_2505_11101
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Nonlocal dielectric properties of water: the role of electronic delocalisation
Labavić, Darka
Brünig, Florian N.
Netz, Roland R.
Bocquet, Marie-Laure
Berthoumieux, Hélène
Chemical Physics
The nonlocal dielectric properties of liquid water are studied in the context of {\it ab initio} molecular dynamics simulations based on density functional theory. We calculate the dielectric response from the charge structure factor of the liquid using the fluctuation-dissipation theorem. We show that the dielectric response function of {\it ab initio} simulations differs significantly from that of classical force-fields, both qualitatively and quantitatively. In particular, it exhibits a larger amplitude and a wider range of responding wave numbers. We suggest that the difference is due to the localisation of the electronic charge density inherent in classical force files and Wannier post-treatment of DFT densities. The localised charge models do not reproduce the shape of the response function even for $q$ corresponding to intermolecular distances, and could lead to a significant underestimation of the dielectric response of the liquid by a factor of 10.
title Nonlocal dielectric properties of water: the role of electronic delocalisation
topic Chemical Physics
url https://arxiv.org/abs/2505.11101