An enhanced version of the heat exchange algorithm with excellent energy conservation properties
- Author(s)
- P. Wirnsberger, D. Frenkel, C. Dellago
- Abstract
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(s)
- Computational and Soft Matter Physics
- External organisation(s)
- University of Cambridge
- Journal
- Journal of Chemical Physics
- Volume
- 143
- No. of pages
- 8
- ISSN
- 0021-9606
- DOI
- https://doi.org/10.1063/1.4931597
- Publication date
- 09-2015
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103036 Theoretical physics, 103015 Condensed matter, 103029 Statistical physics
- Keywords
- ASJC Scopus subject areas
- General Physics and Astronomy, Physical and Theoretical Chemistry
- Sustainable Development Goals
- SDG 7 - Affordable and Clean Energy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/7e26d8c5-aa72-41cd-a698-315b518fae14