Effective thermostat induced by coarse graining of simple point charge water
Artikel i vetenskaplig tidskrift, 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

Författare

Anders Eriksson

Göteborgs universitet

Martin Nilsson Jacobi

Chalmers, Energi och miljö, Fysisk resursteori

Johan Nyström

Chalmers, Energi och miljö, Fysisk resursteori

Kolbjörn Tunström

Chalmers, Energi och miljö

Journal of Chemical Physics

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

Vol. 129 2

Ämneskategorier

Atom- och molekylfysik och optik

DOI

10.1063/1.2953320