Effective thermostat induced by coarse graining of simple point charge water
Journal article, 2008

We investigate how the transport properties of a united atom fluid with a dissipative particle dynamics thermostat depend on the functional form and magnitude of both the conservative and the stochastic interactions. We demonstrate how the thermostat strongly affects the hydrodynamics, especially diffusion, viscosity, and local escape times. As model system we use simple point charge (SPC) water, from which projected trajectories are used to determine the effective interactions in the united atom model. The simulation results support our argument that the thermostat should be viewed as an integral part of the coarse-grained dynamics rather than a tool for approaching thermal equilibrium. As our main result we show that the united atom model with the adjusted effective interactions approximately reproduces the diffusion constant and the viscosity of the underlying detailed SPC water model.

statistical-mechanical theory

liquids

equilibrium

temperature

dissipative particle dynamics

transport

ensemble

simulations

molecular-dynamics

potentials

Author

Anders Eriksson

University of Gothenburg

Martin Nilsson Jacobi

Chalmers, Energy and Environment, Physical Resource Theory

Johan Nyström

Chalmers, Energy and Environment, Physical Resource Theory

Kolbjörn Tunström

Chalmers, Energy and Environment

Journal of Chemical Physics

0021-9606 (ISSN) 1089-7690 (eISSN)

Vol. 129 2 024106

Subject Categories

Atom and Molecular Physics and Optics

DOI

10.1063/1.2953320

More information

Latest update

4/5/2022 6