Applying molecular theory to steady-state diffusing systems

Journal Article · Mon May 01 04:00:00 EDT 2000 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.481376· OSTI ID:20216010

Frink, Laura J. Douglas ^[1]; Thompson, Aidan ^[1]; Salinger, Andrew G ^[2]

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1. Department of Computational Biology and Materials Technology, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)
2. Department of Parallel Computational Sciences, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

Predicting the properties of nonequilibrium systems from molecular simulations is a growing area of interest. One important class of problems involves steady-state diffusion. To study these cases, a grand canonical molecular dynamics approach has been developed by Heffelfinger and van Swol [J. Chem. Phys. 101, 5274 (1994)]. With this method, the flux of particles, the chemical potential gradients, and density gradients can all be measured in the simulation. In this paper, we present a complementary approach that couples a nonlocal density functional theory (DFT) with a transport equation describing steady-state flux of the particles. We compare transport-DFT predictions to GCMD results for a variety of ideal (color diffusion), and nonideal (uphill diffusion and convective transport) systems. In all cases, excellent agreement between transport-DFT and GCMD calculations is obtained with diffusion coefficients that are invariant with respect to density and external fields. (c) 2000 American Institute of Physics.

• OSTI ID: 20216010
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 17 Vol. 112; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
DENSITY
DIFFUSION
MOLECULES
THEORETICAL DATA
TRANSPORT THEORY