---
_id: '10380'
abstract:
- lang: eng
  text: Using non-equilibrium molecular dynamics simulations, it has been recently
    demonstrated that water molecules align in response to an imposed temperature
    gradient, resulting in an effective electric field. Here, we investigate how thermally
    induced fields depend on the underlying treatment of long-ranged interactions.
    For the short-ranged Wolf method and Ewald summation, we find the peak strength
    of the field to range between 2 × 107 and 5 × 107 V/m for a temperature gradient
    of 5.2 K/Å. Our value for the Wolf method is therefore an order of magnitude lower
    than the literature value [J. A. Armstrong and F. Bresme, J. Chem. Phys. 139,
    014504 (2013); J. Armstrong et al., J. Chem. Phys. 143, 036101 (2015)]. We show
    that this discrepancy can be traced back to the use of an incorrect kernel in
    the calculation of the electrostatic field. More seriously, we find that the Wolf
    method fails to predict correct molecular orientations, resulting in dipole densities
    with opposite sign to those computed using Ewald summation. By considering two
    different multipole expansions, we show that, for inhomogeneous polarisations,
    the quadrupole contribution can be significant and even outweigh the dipole contribution
    to the field. Finally, we propose a more accurate way of calculating the electrostatic
    potential and the field. In particular, we show that averaging the microscopic
    field analytically to obtain the macroscopic Maxwell field reduces the error bars
    by up to an order of magnitude. As a consequence, the simulation times required
    to reach a given statistical accuracy decrease by up to two orders of magnitude.
acknowledgement: The authors should like to dedicate this paper to the memory of Simon
  de Leeuw, who was a pioneer in the calculation of Coulomb effects in simulations.
  P.W. would like to thank the Austrian Academy of Sciences for financial support
  through a DOC Fellowship, and for covering the travel expenses for the CECAM workshop
  in Zaragoza in May 2015, where these results were first presented. P.W. would also
  like to thank Chao Zhang for pointing out the equivalence of the two expressions
  for the electric field discussed in Sec. VI D, Michiel Sprik for emphasising the
  importance of the quadrupole contribution in experimental studies of interfacial
  systems, as well as Aleks Reinhardt and other members of the Frenkel and Dellago
  groups for their advice. We further acknowledge support from the Federation of Austrian
  Industry (IV) Carinthia (P.W.), the University of Zagreb and Erasmus SMP (D. Fijan),
  the Human Frontier Science Program and Emmanuel College (A.Š.), the Austrian Science
  Fund FWF within the SFB Vicom project F41 (C.D.), and the Engineering and Physical
  Sciences Research Council Programme Grant No. EP/I001352/1 (D.F.). Additional data
  related to this publication are available at the University of Cambridge data repository
  (http://dx.doi.org/10.17863/CAM.118).
article_number: '224102'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: P.
  full_name: Wirnsberger, P.
  last_name: Wirnsberger
- first_name: D.
  full_name: Fijan, D.
  last_name: Fijan
- first_name: Anđela
  full_name: Šarić, Anđela
  id: bf63d406-f056-11eb-b41d-f263a6566d8b
  last_name: Šarić
  orcid: 0000-0002-7854-2139
- first_name: M.
  full_name: Neumann, M.
  last_name: Neumann
- first_name: C.
  full_name: Dellago, C.
  last_name: Dellago
- first_name: D.
  full_name: Frenkel, D.
  last_name: Frenkel
citation:
  ama: Wirnsberger P, Fijan D, Šarić A, Neumann M, Dellago C, Frenkel D. Non-equilibrium
    simulations of thermally induced electric fields in water. <i>The Journal of Chemical
    Physics</i>. 2016;144(22). doi:<a href="https://doi.org/10.1063/1.4953036">10.1063/1.4953036</a>
  apa: Wirnsberger, P., Fijan, D., Šarić, A., Neumann, M., Dellago, C., &#38; Frenkel,
    D. (2016). Non-equilibrium simulations of thermally induced electric fields in
    water. <i>The Journal of Chemical Physics</i>. American Institute of Physics.
    <a href="https://doi.org/10.1063/1.4953036">https://doi.org/10.1063/1.4953036</a>
  chicago: Wirnsberger, P., D. Fijan, Anđela Šarić, M. Neumann, C. Dellago, and D.
    Frenkel. “Non-Equilibrium Simulations of Thermally Induced Electric Fields in
    Water.” <i>The Journal of Chemical Physics</i>. American Institute of Physics,
    2016. <a href="https://doi.org/10.1063/1.4953036">https://doi.org/10.1063/1.4953036</a>.
  ieee: P. Wirnsberger, D. Fijan, A. Šarić, M. Neumann, C. Dellago, and D. Frenkel,
    “Non-equilibrium simulations of thermally induced electric fields in water,” <i>The
    Journal of Chemical Physics</i>, vol. 144, no. 22. American Institute of Physics,
    2016.
  ista: Wirnsberger P, Fijan D, Šarić A, Neumann M, Dellago C, Frenkel D. 2016. Non-equilibrium
    simulations of thermally induced electric fields in water. The Journal of Chemical
    Physics. 144(22), 224102.
  mla: Wirnsberger, P., et al. “Non-Equilibrium Simulations of Thermally Induced Electric
    Fields in Water.” <i>The Journal of Chemical Physics</i>, vol. 144, no. 22, 224102,
    American Institute of Physics, 2016, doi:<a href="https://doi.org/10.1063/1.4953036">10.1063/1.4953036</a>.
  short: P. Wirnsberger, D. Fijan, A. Šarić, M. Neumann, C. Dellago, D. Frenkel, The
    Journal of Chemical Physics 144 (2016).
date_created: 2021-11-29T11:08:52Z
date_published: 2016-06-10T00:00:00Z
date_updated: 2021-11-29T13:09:08Z
day: '10'
doi: 10.1063/1.4953036
extern: '1'
external_id:
  arxiv:
  - '1602.02734'
  pmid:
  - '27305991'
fulldoi: https://doi.org/10.1063/1.4953036
intvolume: '       144'
issue: '22'
keyword:
- physical and theoretical chemistry
- general physics and astronomy
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1602.02734
month: '06'
oa: 1
oa_version: Preprint
pmid: 1
publication: The Journal of Chemical Physics
publication_identifier:
  eissn:
  - 1089-7690
  issn:
  - 0021-9606
publication_status: published
publisher: American Institute of Physics
quality_controlled: '1'
scopus_import: '1'
status: public
title: Non-equilibrium simulations of thermally induced electric fields in water
type: journal_article
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
volume: 144
year: '2016'
...
