An enhanced version of the heat exchange algorithm with excellent energy conservation properties

Autor(en)

P. Wirnsberger, D. Frenkel, C. Dellago

Abstrakt

We propose a new algorithm for non-equilibrium molecular dynamics simulations of thermal gradients. The algorithm is an extension of the heat exchange algorithm developed by Hafskjold et al. [Mol. Phys. 80, 1389 (1993); 81, 251 (1994)], in which a certain amount of heat is added to one region and removed from another by rescaling velocities appropriately. Since the amount of added and removed heat is the same and the dynamics between velocity

rescaling steps is Hamiltonian, the heat exchange algorithm is expected

to conserve the energy. However, it has been reported previously that

the original version of the heat exchange algorithm exhibits a

pronounced drift in the total energy, the exact cause of which remained

hitherto unclear. Here, we show that the energy drift is due to the

truncation error arising from the operator splitting and suggest an

additional coordinate integration step as a remedy. The new algorithm

retains all the advantages of the original one whilst exhibiting

excellent energy conservation as illustrated for a Lennard-Jones liquid

and SPC/E water.

Organisation(en)

Computergestützte Physik und Physik der Weichen Materie

Externe Organisation(en)

University of Cambridge

Journal

Journal of Chemical Physics

Band

143

Anzahl der Seiten

8

ISSN

0021-9606

DOI

https://doi.org/10.1063/1.4931597

Publikationsdatum

09-2015

Peer-reviewed

Ja

ÖFOS 2012

103036 Theoretische Physik, 103015 Kondensierte Materie, 103029 Statistische Physik

Schlagwörter

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie, Physical and Theoretical Chemistry

Sustainable Development Goals

SDG 7 – Bezahlbare und saubere Energie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/7e26d8c5-aa72-41cd-a698-315b518fae14