English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Random force in molecular dynamics with electronic friction

Hertl, N., Martin-Barrios, R., Galparsoro, O., Larrégaray, P., Auerbach, D. J., Schwarzer, D., et al. (2021). Random force in molecular dynamics with electronic friction. The Journal of Physical Chemistry C, 125(26), 14468-14473. doi:10.1021/acs.jpcc.1c03436.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files
hide Files
:
3349485.pdf (Publisher version), 2MB
Name:
3349485.pdf
Description:
-
Visibility:
Public
MIME-Type / Checksum:
application/pdf / [MD5]
Technical Metadata:
Copyright Date:
-
Copyright Info:
-

Locators

show

Creators

show
hide
 Creators:
Hertl, N.1, Author              
Martin-Barrios, R., Author
Galparsoro, O.1, Author              
Larrégaray, P., Author
Auerbach, D. J.2, Author              
Schwarzer, D.1, Author              
Wodtke, A. M.2, Author              
Kandratsenka, A.1, Author              
Affiliations:
1Department of Dynamics at Surfaces, MPI for Biophysical Chemistry, Max Planck Society, ou_578600              
2Department of Dynamics at Surfaces, MPI for biophysical chemistry, Max Planck Society, ou_578600              

Content

show
hide
Free keywords: -
 Abstract: Originally conceived to describe thermal diffusion, the Langevin equation includes both a frictional drag and a random force, the latter representing thermal fluctuations first seen as Brownian motion. The random force is crucial for the diffusion problem as it explains why friction does not simply bring the system to a standstill. When using the Langevin equation to describe ballistic motion, the importance of the random force is less obvious and it is often omitted, for example, in theoretical treatments of hot ions and atoms interacting with metals. Here, friction results from electronic nonadiabaticity (electronic friction), and the random force arises from thermal electron–hole pairs. We show the consequences of omitting the random force in the dynamics of H-atom scattering from metals. We compare molecular dynamics simulations based on the Langevin equation to experimentally derived energy loss distributions. Despite the fact that the incidence energy is much larger than the thermal energy and the scattering time is only about 25 fs, the energy loss distribution fails to reproduce the experiment if the random force is neglected. Neglecting the random force is an even more severe approximation than freezing the positions of the metal atoms or modelling the lattice vibrations as a generalized Langevin oscillator. This behavior can be understood by considering analytic solutions to the Ornstein–Uhlenbeck process, where a ballistic particle experiencing friction decelerates under the influence of thermal fluctuations.

Details

show
hide
Language(s): eng - English
 Dates: 2021-06-272021-07-08
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1021/acs.jpcc.1c03436
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: The Journal of Physical Chemistry C
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: 125 (26) Sequence Number: - Start / End Page: 14468 - 14473 Identifier: -